Factors of 33
Every whole number that divides 33 exactly, the factor pairs, and how to find them yourself.
The answer
The factors of 33 are 1, 3, 11 and 33.
Factor pairs of 33
| Pair | Makes |
|---|---|
| 1 × 33 | 33 |
| 3 × 11 | 33 |
Prime factors of 33
- Prime factorisation
- 33 = 3 × 11
- Is 33 prime?
- No. It has 4 factors, not just 1 and 33.
- Is 33 a square number?
- No. 5 × 5 = 25 and 6 × 6 = 36, so 33 falls between two square numbers.
How to find the factors of 33
33 is odd, so every even number you try will fail. Its digits add up to 6, a multiple of 3, so 3 is a factor. Work up from 1 to 5, and write down both numbers in every pair you find.
- 33 ÷ 1 = 33, so 1 × 33 is a pair.
- 2 does not go into 33 exactly.
- 33 ÷ 3 = 11, so 3 × 11 is a pair.
- 4 does not go into 33 exactly.
- 5 does not go into 33 exactly.
Stop at 6: 6 × 6 = 36, which is more than 33. The next pair you would find is 11 × 3, which is 3 × 11 turned round, so you already have every pair.
33 in the times tables
3 × 11 = 33. Practise the 3 times table and 11 times table.
More numbers
Check whether 33 is prime.
Questions parents ask
What is the largest factor of 33, apart from 33 itself?
11. Divide 33 by its smallest factor above 1, which is 3: 33 ÷ 3 = 11.
What do the factors of 33 add up to?
48. Leaving out 33 itself, they add up to 15, which is less than 33, so 33 is called a deficient number.
Which number after 33 has the same number of factors?
34. Like 33, 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.