What are prime numbers?

Prime numbers are special numbers, greater than 1, that have exactly two factors, themselves and 1.

19 is a prime number. It can only be divided by 1 and 19.

9 is not a prime number. It can be divided by 3 as well as 1 and 9.

The prime numbers below 20 are:

2, 3, 5, 7, 11, 13, 17, 19

The number 1 is not a prime number as it only has one factor.

Looking for even more resources to help engage students in your maths lessons? Get stuck into Prime numbers, composite numbers and factors with the Prime Suspects in this animated short clip.

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