The online computer game “Is this prime?” tests a player’s knowledge of prime numbers—and just surpassed 2,999,999 attempts. Give it a whirl. The Greek mathematician Euclid may very well have proved, ...

In context: Prime numbers are those divisible only by 1 and themselves and include mathematical oddballs like 2, 3, 5, 7, and 11. While they start out simple, primes rapidly become sparse amid the ...

Prime numbers, whole numbers greater than one with only two factors (one and themselves), are fundamental in mathematics. They serve as building blocks for all other whole numbers, a concept known as ...