The Odds Are Against Even Numbers

There’s something odd about our arithmetic. Like Rodney Dangerfield, even numbers don’t get no respect.

Start with prime numbers. A prime number has only two factors, meaning it is divisible only by itself and 1. Except for 2, the token even number in the lot, the prime numbers—3, 5, 7, 11, etc.—are all odd. Prime numbers have a certain mystical allure, a flair that other numbers lack. Amazon calls its elite service “Prime.” The word connotes status and superiority.