A **PRIME **number is one that **only has two factors**, itself and 1.

A **COMPOSITE **number is one that has **more than two factors**.

**PRIME** numbers include 2, 3, 5, 7, 11, 13, 17 etc....

**COMPOSITE** numbers include 4, 6, 8, 9, 10, 12, 14, 15 etc....

**Example 1**

Is the following number prime or composite?

13

**Answer**

13 = 13 × 1

No other whole numbers multiply together to make 13.

The numbers that go into 13 exactly are called its factors.

13 only has the two factors of 13 and 1 and so it is **prime**.

**Example 2**

Is the following number prime or composite?

12

**Answer**

12 = 12 × 1

12 = 6 × 2

12 = 4 × 3

The numbers that go into 12 exactly are called its factors.

12 has factors of 12, 6, 4, 3, 2 and 1 and so it is **composite**.