In the middle of class today (*History of Math*, full of Junior math majors) one of my students asked out of the blue “What’s your favorite number?” I said it was 4, because back when I was in elementary school there was a joke that went around where Person A would ask Person B for their favorite color, favorite animal, and favorite number. After Person B replied, Person A would come back with something like, “You’re going to marry a purple dog with 7 legs. HAHAHAHAHA!!!!!!!” The idea of a blue cat with anything other than 4 legs really bothered me, so my favorite number immediately became 4. The fact that I was going to marry a blue cat apparently didn’t cause any angst at all.

This quickly evolved into me asking my class their favorite numbers. And not only did every single person have one, but they all had clearly thought about this. One person also liked 4, but explained it was the ONLY even number she liked. Other than 4, she really hated even numbers. Just hated them. One person liked 24 because it was her birthday. Two people liked numbers (1 and 30) because they was their jersey numbers. One person had two favorites: 6 and 27. One person liked 144 because (1+4+4)×(1×4×4)=144. [This only works for 0, 1, 135, and 144. Isn’t that cool?] And 19 was the favorite number of not one, but two people. For some reason that struck me as a dark and sophisticated favorite number to have. It’s so….prime.

Now I’m feeling all jealous of everyone else’s favorite numbers and thinking I should let go of the whole elementary school thing. I’ve noticed that I’ve used 87 three times in the last two days as a synonym for “a lot” [as in, “You can reach me by email because I check 87 times a day”] so maybe 87 is my subconscious favorite number.

What’s yours? Why?

(The Onion had this question in a survey back in 1996. I was living in Madison at the time and saved it, but can’t find it now — it’s somewhere in the Archaeological Dig that is my desk. But you can see it the results online here.)