Learn that and more with these fun facts about the number 13 (seven of them, in case you're looking for good luck).
Fear of the number has a name
It's called triskaidekaphobia. There's also a more specific fear of Friday the 13th, friggatriskaidekaphobia. There's even a treatment center for those who suffer from these irrational fears. Friggatriskaidekaphobia Treatment Center in Pocopson, Pa. offers "clever games, costumed hosts, exhibits of silly superstitions, anti-superstition music and free educational literature."
Superstitions around the number have biblical origins
One explanation for society's fear of the number 13 stems from the Bible. It's said that if 13 people share a meal at a table together, one of the diners will die within a year. Nathaniel Lachenmeyer, who wrote a book about the number 13, said this superstition originated from the Last Supper with Jesus and his 12 disciples shortly before his death.
Murderers carry 13-letter names
A number of serial killers and notorious murderers have names with 13 letters, Mental Floss points out, including Charles Manson and Jack the Ripper.
Julia Louis-Dreyfus and other celebs were born on Friday the 13th
Being born on an "unlucky" day didn't slow these celebrities' careers. Julia Louis-Dreyfus, the Emmy-winning star of VEEP and Seinfeld, was born on Jan. 13, 1961. Celebrities also born on Friday the 13th include Mary-Kate and Ashley Olsen and Steve Buscemi.
Historic superstition-defiers formed a secret club
Captain William Fowler, an enthusiastic embracer of the power of 13, founded a secret supper club in celebration of the number in 1882, according to the New York Historic Society. Called the 13 Club, its first meeting included 13 courses, was lit by 13 candles and was attended (of course) by 13 people. The club continued its unlucky meetings throughout the late 1800s and early 1900s, and its honorary members included presidents Chester A. Arthur, Grover Cleveland, Benjamin Harrison, and Theodore Roosevelt.
Tuesday the 13th can be bad luck, too
It's not just Friday the 13th that puts superstitious people on edge. In some Spanish-speaking countries, the day of bad luck is actually Tuesday. The movie Friday the 13th was even translated into Martes Tres (Tuesday the 13th) for its global release.
Taylor Swift has called it lucky
The singer was born on the 13th, turned 13 on Friday the 13th, her first album went gold in 13 weeks, and her first #1 song had a 13 second intro. Swift also says every time she's won an award she has been sitting in either the 13th row, 13th seat, 13th section or row M, which is the 13th letter, according to MTV.