🔢 Number Theory

Factor Calculator

Find all factors (divisors) of any positive integer — including factor pairs, proper divisors, prime factors, and whether the number is prime, perfect, abundant, or deficient.

Find All Factors

Enter a positive integer above
Factors are numbers that divide evenly into the given number.

Frequently Asked Questions

What is a factor?
A factor (or divisor) of a number n is any positive integer that divides n with no remainder. For example, the factors of 12 are 1, 2, 3, 4, 6, and 12 — because 12 ÷ 1 = 12, 12 ÷ 2 = 6, etc.
What is a perfect number?
A perfect number equals the sum of its proper divisors (all factors excluding itself). The smallest perfect number is 6: proper divisors are 1, 2, 3 and 1+2+3 = 6. The next are 28, 496, and 8128.