Factors of 11
Every whole number that divides 11 exactly, the factor pairs, and how to find them yourself.
The answer
The factors of 11 are 1 and 11. 11 is a prime number.
Factor pairs of 11
| Pair | Makes |
|---|---|
| 1 × 11 | 11 |
Prime factors of 11
- Prime factorisation
- 11 = 11
- Is 11 prime?
- Yes. It is the 5th prime number.
- Is 11 a square number?
- No. 3 × 3 = 9 and 4 × 4 = 16, so 11 falls between two square numbers.
How to find the factors of 11
11 is prime, so the only pair you will find is 1 × 11. Work up from 1 to 3, and write down both numbers in every pair you find.
- 11 ÷ 1 = 11, so 1 × 11 is a pair.
- 2 does not go into 11 exactly.
- 3 does not go into 11 exactly.
Stop at 4: 4 × 4 = 16, which is more than 11. The next pair you would find is 11 × 1, which is 1 × 11 turned round, so you already have every pair.
More numbers
Check whether 11 is prime.
Questions parents ask
What is the largest factor of 11, apart from 11 itself?
1. 11 is prime, so apart from 11 itself its only factor is 1.
What do the factors of 11 add up to?
12. Leaving out 11 itself, they add up to 1, which is less than 11, so 11 is called a deficient number.
Which number after 11 has the same number of factors?
13. Like 11, it has exactly 2 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.