Factors of 23
Every whole number that divides 23 exactly, the factor pairs, and how to find them yourself.
The answer
The factors of 23 are 1 and 23. 23 is a prime number.
Factor pairs of 23
| Pair | Makes |
|---|---|
| 1 × 23 | 23 |
Prime factors of 23
- Prime factorisation
- 23 = 23
- Is 23 prime?
- Yes. It is the 9th prime number.
- Is 23 a square number?
- No. 4 × 4 = 16 and 5 × 5 = 25, so 23 falls between two square numbers.
How to find the factors of 23
23 is prime, so the only pair you will find is 1 × 23. Work up from 1 to 4, and write down both numbers in every pair you find.
- 23 ÷ 1 = 23, so 1 × 23 is a pair.
- 2 does not go into 23 exactly.
- 3 does not go into 23 exactly.
- 4 does not go into 23 exactly.
Stop at 5: 5 × 5 = 25, which is more than 23. The next pair you would find is 23 × 1, which is 1 × 23 turned round, so you already have every pair.
More numbers
Check whether 23 is prime.
Questions parents ask
What is the largest factor of 23, apart from 23 itself?
1. 23 is prime, so apart from 23 itself its only factor is 1.
What do the factors of 23 add up to?
24. Leaving out 23 itself, they add up to 1, which is less than 23, so 23 is called a deficient number.
Which number after 23 has the same number of factors?
29. Like 23, 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.