How do you find how many proper divisors 7920 has?

Answer 1

12ème

Answer 2

To find the number of divisors of a number, factor it into primes in power format; then the number of factors the number has is the product of the powers of the primes each incremented by 1. To find the proper divisors subtract one from thin number.

The prime factorization of 7920 is 2^4 x 3^2 x 5 x 11, so it has (4 + 1) × (2 + 1) × (1 + 1) × (1 + 1) = 5 × 3 × 2 × 2 = 60 factors. As this includes the number itself and the proper factors of a number exclude the number, 7920 has 60 - 1 = 59 proper factors (divisors).