Prime Numbers
Maths: Year 5 & 6 National Curriculum, topic 1.3.3
Prime Numbers
A prime number only has 2 factors. The factors of a prime number are 1 and the prime number itself.
2 is a prime number
- The factors of 2 are 1 and 2.
- 2 is a prime number because it only has 2 factors.
3 is a prime number
- The factors of 3 are 1 and 3.
- 3 is a prime number because it only has 2 factors.
4 is NOT a prime number
- The factors of 4 are 1, 2 and 4.
- 4 is NOT a prime number because it has more than 2 factors.
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Prime numbers up to 20
- There are both big and small prime numbers.
- The prime numbers below 20 are shown here.
Prime numbers up to 20
- Notice that all of the prime numbers are odd numbers except the number 2.
- All of the prime numbers are odd (apart from 2) because even numbers are in the 2 times table (and so have more than 2 factors).
Test yourself on Prime Numbers
Is 2 a prime number?
Is 15 a prime number?
Apart from 2, are there any EVEN prime numbers?