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Is 32 a prime number?

32 is not a prime number. Here is the quickest way to see it.

The answer

No. 32 is not a prime number: 2 × 16 = 32.

How to see that 32 is not prime

32 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 32.

32 has 6 factors (1, 2, 4, 8, 16 and 32), which make 3 factor pairs.

Split 32 into prime factors

Split off the smallest prime each time, and keep going until every part is prime:

  1. 32 = 2 × 16
  2. 32 = 2 × 2 × 8
  3. 32 = 2 × 2 × 2 × 4
  4. 32 = 2 × 2 × 2 × 2 × 2

With the repeated primes written as powers, that is 2⁵.

32 in the times tables

32 turns up in 2 different times tables, the 4 and 8: 4 × 8 and 8 × 4.

Quick checks that catch 32

  • The last digit, 2, is even, so 2 goes in.
  • Half of it is 16, which is still even, so 4 goes in.

32 at a glance

In words
thirty-two
In Roman numerals
XXXII
Odd or even
Even: it ends in 2
Its factors add up to
63, or 31 without 32 itself, which makes 32 a deficient number

The numbers either side of 32

  • 31 is prime: 2, 3 and 5 do not go into it, and 7 × 7 is already past 31. Check 31 in full
  • 33 is not prime. Its digits add up to 3 + 3 = 6, which is a multiple of 3. That means 33 is a multiple of 3 too, so 3 is a factor. Check 33 in full

Turn the digits round

32 backwards is 23. 23 is prime: 2 and 3 do not go into it, and 5 × 5 is already past 23. Check 23 in full

Related pages

More numbers

Questions parents ask

Which prime numbers are either side of 32?

31 below it and 37 above it, a gap of 6.

What is 32 squared?

32 × 32 = 1024.

What is the smallest number with as many factors as 32?

12. It has 6 factors, the same as 32.

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.