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Is 35 a prime number?

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

The answer

No. 35 is not a prime number: 5 × 7 = 35.

How to see that 35 is not prime

35 ends in 5, and every number ending in 5 or 0 is in the 5 times table, so 5 is a factor.

35 has four factors: 1 and 35, plus one pair in between, 5 and 7.

Split 35 into prime factors

35 splits straight into two primes, 5 × 7, so its factor tree has only one branch.

35 in the times tables

35 turns up in 2 different times tables, the 5 and 7: 5 × 7 and 7 × 5.

Quick checks that catch 35

  • It ends in 5, so 5 goes in.

35 at a glance

In words
thirty-five
In Roman numerals
XXXV
Odd or even
Odd: it ends in 5
Its factors add up to
48, or 13 without 35 itself, which makes 35 a deficient number

The numbers either side of 35

  • 34 is not prime. 34 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 34. Check 34 in full
  • 36 is not prime. 36 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 36. Check 36 in full

Turn the digits round

35 backwards is 53. 53 is prime: 2, 3, 5 and 7 do not go into it, and 11 × 11 is already past 53. Check 53 in full

Related pages

More numbers

Questions parents ask

Which prime numbers are either side of 35?

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

What is 35 squared?

35 × 35 = 1225.

What is the smallest number with as many factors as 35?

6. It has 4 factors, the same as 35.

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.