**The only even prime number is two.** A prime number can only be divided by itself and one.

Two is a prime number because its only factors are 1 and itself. It is an even number as well because it can be divided by 2. All of the other prime numbers are odd, including 3, 5, 7, 11 and 13. Every number has factors of 1 and itself, but prime numbers have no other factorization possibilities. Composite numbers are those that are not prime; in other words, they have more than one factorization. For example, 8 is a composite number, because it has factors of 1 and 8 and 2 and 4.