Is 26 a prime number?
26 is not a prime number. Here is a way to check it.
The answer
No. 26 is not a prime number: 2 × 13 = 26.
How to see that 26 is not prime
26 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 26.
26 has four factors: 1 and 26, plus one pair in between, 2 and 13.
Split 26 into prime factors
26 splits straight into two primes, 2 × 13, so its factor tree has only one branch.
26 in the times tables
No fact from the 2 to 12 times tables, up to × 12, makes 26. Its smallest pair, 2 × 13, needs the 13 times table, which goes past 12.
See the 13 times table, where 13 × 2 = 26 is one of the facts.
Quick checks that catch 26
- The last digit, 6, is even, so 2 goes in.
26 at a glance
Optional extra number facts:
- In words
- twenty-six
- In Roman numerals
- XXVI
- Odd or even
- Even: it ends in 6
- Its factors add up to
- 42, or 16 without 26 itself. 26 is deficient: Deficient means this sum is less than the number.
The numbers either side of 26
- 25 is not prime. 25 ends in 5, and every number ending in 5 or 0 is in the 5 times table, so 5 is a factor. Check 25 in full
- 27 is not prime. Its digits add up to 2 + 7 = 9, which is a multiple of 3. That means 27 is a multiple of 3 too, so 3 is a factor. Check 27 in full
Turn the digits round
26 backwards is 62. 62 is not prime. 62 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 62. Check 62 in full
Related pages
More numbers
Questions parents ask
Which prime numbers are either side of 26?
23 below it and 29 above it, a gap of 6.
What is 26 squared?
26 × 26 = 676.
What is the smallest number with as many factors as 26?
6. It has 4 factors, the same as 26.
Continue your number practice
Explore the diagnostic for another set of practice questions.