Factors of 8
Every whole number that divides 8 exactly, the factor pairs, and how to find them yourself.
The answer
The factors of 8 are 1, 2, 4 and 8.
Factor pairs of 8
| Pair | Makes |
|---|---|
| 1 × 8 | 8 |
| 2 × 4 | 8 |
Prime factors of 8
- Prime factorisation
- 8 = 2 × 2 × 2 (2³)
- Is 8 prime?
- No. It has 4 factors, not just 1 and 8.
- Is 8 a square number?
- No. 2 × 2 = 4 and 3 × 3 = 9, so 8 falls between two square numbers.
How to find the factors of 8
8 is even, so 2 is sure to be a factor. Work up from 1 to 2, and write down both numbers in every pair you find.
- 8 ÷ 1 = 8, so 1 × 8 is a pair.
- 8 ÷ 2 = 4, so 2 × 4 is a pair.
Stop at 3: 3 × 3 = 9, which is more than 8. The next pair you would find is 4 × 2, which is 2 × 4 turned round, so you already have every pair.
8 in the times tables
2 × 4 = 8. Practise the 2 times table and 4 times table.
More numbers
Check whether 8 is prime.
Questions parents ask
What is the largest factor of 8, apart from 8 itself?
4. Divide 8 by its smallest factor above 1, which is 2: 8 ÷ 2 = 4.
What do the factors of 8 add up to?
15. Leaving out 8 itself, they add up to 7, which is less than 8, so 8 is called a deficient number.
Which number after 8 has the same number of factors?
10. Like 8, it has exactly 4 factors.
Number facts are the base of 11+ maths
Factors, multiples, primes and square numbers come up all over 11+ maths, from simplifying fractions to ratio. The free diagnostic checks maths, English and both kinds of reasoning, and shows what to practise next. No card is required.