Most mathematicians will tell you that numbers have no moral value; they simply are what they are. But the vast array of superstitions about numbers from around the globe might beg to differ: Depending on where in the world you are, specific numbers might be considered lucky; others might be viewed as unlucky; and in some cases, some numbers might even indicate the presence of some sort of otherworldly power.
The thing to remember about superstitions is that the cultural context in which they appear matters. It matters a lot. The number 13, for instance? Sure, it’s widely regarded as unlucky in many Western cultures—a belief that has murky origins. Still, it may have something to do with the number of guests at both the Last Supper as described in the Bible and the party at which Baldur was killed in Norse mythology (not to mention a certain long-running American film franchise). But in other places, it’s viewed neutrally or even positively.
Many other numbers might have connotations you may not have considered before, as well, depending on where you’re from or where you’ve spent time traveling. These seven numbers, for instance, might bring you good fortune, signify ill omens, or even tell you something you didn’t know about yourself—if you believe in them, that is.
3 Is for Luck
In a wide variety of places, the number three is tied up with luck—both good and bad.
When it comes to good luck, many English-speaking regions have the saying that the “third time is the charm”—a phrase that’s often trotted out as a good luck charm, meaning that the third time you attempt to do something or perform a particular action, the more likely you are to succeed in it. It’s not known exactly where this saying comes from. Still, according to Phrases.org.uk, one of the earliest written precursors to it appears in a letter English poet Elizabeth Barrett Browning wrote to poet and critic Richard Henry Horne in 1839: “‘The luck of the third adventure’ is proverbial,” she wrote.
However, there’s also a belief in a few places that it’s an ill omen to light three cigarettes on one match. In the United States, the superstition can be traced back to the early decades of the 20th century; it states both that it’s generally bad luck to light “three on a match,” as well that the third person to light their cigarette from the match in question will die. In Mexico, however, all three people who light on a single match are said to be in danger: According to this superstition, bad luck will come for one of them, although it’s not always immediately apparent which one. The “three on a match” superstition in some ways echoes a common belief that bad things come in threes—or, sometimes, that notable deaths come in threes.
Meanwhile, a superstition in Vietnam also paints the number three in an ill-favored light. As David Lamb reported for the Los Angeles Times in 2000, Vietnamese folkloric beliefs tend to arise out of “a mixture of Buddhism, Confucian theology, local tradition, paganism, and ancestor worship.” According to one belief, in particular, three people should never pose for a photograph together. If they do, the person in the middle will suffer bad luck in the near future.
4 Is for Death
As Haru Yamada, Orlando R. Kelm, and David A. Victor note in their book The 7 Key Ways to Communicating in Japan: An Intercultural Approach, the number four sounds quite similar to the words for “death” in many East Asian languages. In Japanese specifically, for example, the character 四, which represents the number four, is an exact homonym with the character 死, or “death.” Both are both pronounced “shi.” The same is true in China, where the character for the number four is also 四; pronounced “sì,” it sounds shockingly similar to the character 死, pronounced “sǐ” and meaning “death.”
Accordingly, the number four is not just treated with suspicion; it’s straight-up avoided whenever possible. In countries and cultures with this superstition, many hotels, hospitals, and other buildings are built without fourth floors, similarly to how structures in the United States are often built without 13th floors. When the floors are numbered, they jump right from three to five, skipping four in between or labeling it the “mezzanine.” Essential meetings or events are rarely scheduled on dates that end in four, and never, ever on April 4. Items for sale will virtually ever be found grouped in boxes of four. Even license plate numbers can be affected.
7 Is for Sons
“The seventh son of a seventh son” —that is, the seventh son born of a parent who is themself a seventh son—is said in many cultures to have a wide variety of powers and abilities; precisely what those powers and abilities are, though, depends on who you talk to.
According to some cultures, seventh children of seventh children are literally monsters. In Argentina, for example, there’s a legend that states that seventh sons are particularly prone to falling to the curse of the lobizón—essentially a werewolf. (It should be noted, though, that this legend is unrelated to the Argentinian tradition of presidential sponsorship, in which the seventh child born in every family of seven or more children in Argentina becomes the president’s godchild—as several news outlets discovered after misreporting a story melding the lobizón legend with the presidential sponsorship tradition in 2014.) Similarly, in Romanian folklore, a human can be born a strigoi—a type of vampire—if they’re the seventh son of a seventh son.
However, in Scotland and Cornwall, being the seventh child of a seventh child is quite a positive thing. According to the Encyclopedia of Superstitions by E. and M.A. Radford, seventh children born in these areas have innate healing talents and abilities; indeed, it’s said that such children are destined to be doctors. They’re also said to have “second sight” or prophetic abilities—or simply to have an unusual amount of luck.
8 Is for Prosperity
Just as many East Asian cultures view the number four with suspicion due to its linguistic quirks, so, too, is the number eight viewed favorably for similar reasons. In addition to dates and times involving the number eight being popular choices for important meetings and events, many who ascribe to this belief will go out of their way to include the number in their addresses, phone numbers, and even license plate numbers.
The common theme? Prosperity. For instance, in China, the number eight is represented with the character 八. Pronounced “ba,” the number sounds similar to the pronunciation of the character 發 (“fa”), which can be translated as “wealth” or “fortune.” The more eights there are, the better; that’s actually why the 2008 Summer Olympics in Beijing opened at 8:00 p.m. on Aug. 8—the idea was to kick things off at a particularly auspicious time. Meanwhile, in Japan, the number eight gets its magic not only from its pronunciation but from its appearance. It’s represented with the character 八 (pronounced “hachi”), which widens at the base, thereby symbolizing prosperity and growth.
9 Is for Suffering
But although eight is an omen of prosperity, nine is not—and in a range of cultures, to boot. The 7 Keys to Communicating in Japan points out that the number nine in Japanese is another homonym: Represented with the character 九 and pronounced “kyu,” it sounds quite close to 苦, pronounced “ku,” which means “suffering.”
Neither is Japan the only place where the number nine is considered to be inauspicious. In the world of classical music—particularly the world of European classical music—the “curse of the ninth” warns composers about what might await them after they complete their eight symphony. Should they go on to write a ninth, it might well be their last.
Ludwig von Beethoven is frequently cited as the most famous victim of the alleged “curse”; he died in 1827, just three years after completing his Ninth Symphony. Gustav Mahler is also said to have attempted to thwart the curse. He supposedly disguised the work between his official Eighth and Ninth Symphonies, Das Lied von der Erde, as a song cycle (even though it’s structurally a symphony), hoping that he’d be able to escape the curse. Alas, though, he died in 1911, leaving his Tenth Symphony unfinished.
Of course, it’s been pointed out time and time again that many composers have written more than nine symphonies. Many composers often included in lists of victims of the alleged curse don’t quite fit the criteria. And, perhaps most importantly, Mahler would only have known of two alleged “victims”—Beethoven and Anton Bruckner—which many don’t believe sufficient numbers to have stoked fear of a curse in Mahler himself. Even so, the “curse of the ninth” remains a popular piece of musical folklore.
17 Is for the End of it All
In Italy, the number 13 is actually good luck—but the number 17? That’s the number to avoid at all costs. Indeed, instead of Friday the 13th, it’s said that Friday the 17th is a day to watch out for.
A few different explanations are floating around for why 17 is considered to be so inauspicious in Italy, but one of the most frequently cited dates the superstition back to antiquity. It has to do with the way 17 is represented in Roman numerals: XVII. If you rearrange the letters that make up that representation just slightly, the resulting word is “vixi” —that is, “I have lived.” As Emma Law put it at Culture Trip in 2018, “Some consider this a bad omen as it implies that death is just around the corner.”
Another possible explanation ties into the fact that Catholicism is the predominant religion in Italy. Michael San Filippo noted at ThoughtCo. in 2019 that, per the Bible’s Old Testament, “the great flood happened on the 17th day of the month,” thereby making it quite an unlucky day, indeed—and as for why Friday the 17th is considered particularly bad luck? That’s because of Good Friday, the day on which Jesus is said to have died.
87 Is for the Devil
The number 87 has quite a diabolical reputation in Australia—especially if you follow cricket: It’s considered the “devil’s number.” Why? In some ways, it’s a riff on the idea that 13 is an unlucky number; a score 87 in the sport of cricket is 13 runs short of what’s called a century—a score of 100 runs which is considered to be a particular milestone for players of the game.
Legend has it that the superstition can be traced to one player: Keith Miller, who is considered to be the best all-round cricketer Australia has ever seen. In 1929, when Miller 10 years old, he watched in shock as his hero, Don Bradman, was dismissed from the field after being bowled neck and crop (roughly equivalent to being given an out in baseball) at 87 runs. Years later, when Miller was playing for South Melbourne, he witnessed fellow player Ian Johnson be dismissed on 87, as well. In response, Miller shared a theory he’d been developing about the number 87 being an unlucky number in cricket based on his anecdotal experience—and from there, the superstition snowballed.
There was just one problem. Miller later found out that Bradman had actually been bowled on 89, not 87. By that point, though, the legend was cemented and 87 painted as the devil’s number.
Do any of these numbers really have the power ascribed to them? Only you can decide that for yourself. But, well, it couldn’t hurt to avoid grouping things in fours from here on out, right?