## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

All numbers have at least two factors, $1$, and themselves. While composite numbers have more than that, prime numbers only have those two. Example: $7$ is a prime number because you can only divide it evenly by two numbers $1$, and itself, $7$. $9$, however, it a composite number because while like every number it can be divided by $1$, and itself, $9$, it can also be divided by $3$.