1 - No number from 1 to 999 includes the letter "a" in its word form.
(Unless you live in the United Kingdom where it's proper to write 101 as "one hundred and one," there is no number from 1 to 999 that includes the letter "a" in its word form, according to longtime math teacher Jonathan Garnett-Smith. One, two, three, four, five, six… twenty, thirty, forty, fifty, sixty… You can keep going, but you won't find the first letter of the alphabet until you hit "one thousand.")

2 - The opposite sides of a die will always add up to seven.
(If you take a look, you'll see that one and six are on opposite sides of the cube (1+6=7), as are two and five (2+5=7), and three and four (3+4=7). And if you want to understand more about this amazing but useless fact, The Guardian offers a deeper explanation.)

3 - You are 13.8 percent more likely to die on your birthday.
(According to a 2012 study published in the journal Annals of Epidemiology, humans are 13.8 percent more likely to die on their birthday than on any other day of the year. That's according to Swiss mortality statistics from 1969 to 2008. We've got to say, that study is (morbidly) interesting!)

4 - The King of Hearts is the only king in a deck of cards without a mustache.
(There are four kings in every deck of cards. And while they all look similar, the King of Hearts is the only royal fellow who doesn't have a mustache. According to The Guardian, the so-called "suicide king" (who earned his name because it looks like he's stabbing himself in the head with a sword) wasn't always bare-faced. He mistakenly lost his facial hair in a redesign.)

5 - "Dreamt" is the only word in the English language that ends with "mt."
(The English language is full of idiosyncrasies, and the word "dreamt" is one of them. According to Oxford Dictionaries, "dreamt" (and its variations, such as "undreamt") is the only word in the English language that ends with the letters "mt.")

6 - Those metal studs on your jeans have a name and a purpose.
(The next time you're wearing a pair of jeans, take a look at the pockets. Do you see those little metal studs on the corners? They're not just there to add some extra pizzazz to your pants; they actually have a purpose. These rivets, according to Levi Strauss & Co., are placed on certain spots to add extra support where the denim is more likely to wear out and rip.)

7 - A Greek-Canadian man invented the "Hawaiian" pizza.
(There will always be fierce debates over whether or not pineapple has any place on a pizza, but there's no question about where the Hawaiian pizza originally came from: Chatham, Ontario, Canada! Restaurant owner Sam Panopoulos was born in Greece but moved to Canada when he was 20 years old. And in 1962, the entrepreneur decided to put pineapple on pizza.

Panopoulos, who passed away in 2017, once told the BBC, "We just put it on, just for the fun of it, see how it was going to taste. We were young in the business and we were doing a lot of experiments." The name apparently came from the brand of canned pineapple that Panopoulos used on that fateful day he invented the Hawaiian pizza.)

8 - Alaska is the only state whose name is on one row on a keyboard.
(With "A" and "S" being beside each other on the middle row of the standard QWERTY keyboard and "K" and "L" over on the other side of the same row, Alaska is the only state name that you can type out using a single row on a keyboard.)

9 - And "tesseradecades," "aftercataracts," and "sweaterdresses" are the longest words you can type using only your left hand.
(If you find yourself only able to use the left side of your computer's keyboard, there are still plenty of words that you can type out. By using Q, W, E, R, T, A, S, D, F, G, Z, X, C, V, and B—the letters on the left side of the standard keyboard—you can not only tap out whoppers like "tesseradecades," "aftercataracts," and "sweaterdresses," you can also type "great," "vast," "water," "starter," "cascades," "retracts," "affects," "trees," "caves," "crests," "waver," "reverberate," "sat," "far," "raced," "faster," "created," "craters," "graves," "wasted," "arrested," and (perhaps best of all) "abracadabra!")

10 - Mulan has the highest kill-count of any Disney character.
(Mulan is fierce, brave, and incredibly inspirational. But she's also incredibly deadly. In fact, she was not only the first Disney princess to kill someone on-screen in the 1998 film Mulan, but she also has the highest kill-count of any Disney character, according to UNILAD. Mulan took out nearly 2,000 people over the course of the animated film, including the evil Hun leader, Shan Yu, and 1,994 Huns by triggering an avalanche.)