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Prime Numbers and Composite Numbers

Note: This is only about whole numbers (integers) greater than 1
In other words: 2,3,4,5,6,7,8,9,10,11,12,... etc

A Prime Number can be divided evenly only by 1, or itself.

A Composite Number can be divided evenly by numbers other than 1 or itself.

(So, any whole number greater than 1 is either prime or composite)

Examples

Number
Can be Evenly
Divided By
Prime, or
Composite?
1
(1 is not considered prime or composite)
2
1,2
Prime
3
1,3
Prime
4
1,2,4
Composite
5
1,5
Prime
6
1,2,3,6
Composite
7
1,7
Prime
8
1,2,4,8
Composite
9
1,3,9
Composite
10
1,2,5,10
Composite

Factors

"Factors" are the numbers you multiply to get another number:

Some numbers can be factored in many ways:

If there is only one way to factor a number, it is a prime number; if there are many ways it is a composite number.