Factors of 77
Every whole number that divides 77 exactly, the factor pairs, and how to find them yourself.
The answer
The factors of 77 are 1, 7, 11 and 77.
Factor pairs of 77
| Pair | Makes |
|---|---|
| 1 × 77 | 77 |
| 7 × 11 | 77 |
Prime factors of 77
- Prime factorisation
- 77 = 7 × 11
- Is 77 prime?
- No. It has 4 factors, not just 1 and 77.
- Is 77 a square number?
- No. 8 × 8 = 64 and 9 × 9 = 81, so 77 falls between two square numbers.
How to find the factors of 77
77 is odd, so every even number you try will fail. Work up from 1 to 8, and write down both numbers in every pair you find.
- 77 ÷ 1 = 77, so 1 × 77 is a pair.
- 2 does not go into 77 exactly.
- 3 does not go into 77 exactly.
- 4 does not go into 77 exactly.
- 5 does not go into 77 exactly.
- 6 does not go into 77 exactly.
- 77 ÷ 7 = 11, so 7 × 11 is a pair.
- 8 does not go into 77 exactly.
Stop at 9: 9 × 9 = 81, which is more than 77. The next pair you would find is 11 × 7, which is 7 × 11 turned round, so you already have every pair.
77 in the times tables
7 × 11 = 77. Practise the 7 times table and 11 times table.
More numbers
Check whether 77 is prime.
Questions parents ask
What is the largest factor of 77, apart from 77 itself?
11. Divide 77 by its smallest factor above 1, which is 7: 77 ÷ 7 = 11.
What do the factors of 77 add up to?
96. Leaving out 77 itself, they add up to 19, which is less than 77, so 77 is called a deficient number.
Which number after 77 has the same number of factors?
82. Like 77, it has exactly 4 factors.
Continue your number practice
Explore the diagnostic for another set of practice questions.