- 4 is a composite number. It can be divided exactly by 1, 2 and 4. 4 is a composite number because it can be divided by 2 (which is not 1 or 4 itself).
- 5 is
**not**a composite number. It can only be divided exactly by 1 and 5. 5 is a prime number because it can only be divided by 1 and 5 itself.

## Dictionary Definition

The Oxford English Dictionary defines a composite number as "a number which is the product of two or more factors, greater than unity."## The Composite Numbers

The composite numbers are:In a number square, the composite numbers are shaded below:**Note**: This is the exact inverse of the prime numbers in a square. If this number square is overlaid with that of the prime numbers, all numbers (apart from 1) would shaded.

## Composite Numbers Are Natural Numbers Greater Than 1

Composite numbers are natural numbers (the counting numbers: 1, 2, 3...) greater than 1.## Interactive Game on Composite Numbers

Here is an interactive game to help you learn about composite numbers.- You are the fish.
- Pop the bubbles with composite numbers to collect red hearts. You need five to win.
- If a bubble with a composite number reaches the top, you will lose a red heart.
- Avoid the bubbles with prime numbers (i.e., non-composite numbers). If you pop one, you will lose one of your three lives.
- Good luck!
- The fish moves towards your clicks. (Hint: The farther the distance, the faster it moves.)

## Factors

Numbers that divide exactly into another number are called factors. For example, the factors of 4 are 1, 2 and 4 because they all divide exactly into 4. Composite numbers must have more than 2 factors: 1, the composite number itself, and at least one other factor. This is in distinction to prime numbers which only have two factors: 1 and the prime number itself.## You might also like...

#### Help Us Improve Mathematics Monster

- Do you disagree with something on this page?
- Did you spot a typo?

__this form__.

#### Find Us Quicker!

- When using a search engine (e.g., Google, Bing), you will find Mathematics Monster quicker if you add
**#mm**to your search term.

#### Share This Page

If you like Mathematics Monster (or this page in particular), please link to it or share it with others.

If you do, __please tell us__. It helps us a lot!

#### Create a QR Code

Use our handy widget to create a QR code for this page...or any page.