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Factor Calculator

Find all factors of a whole number, count them, list every factor pair, and get the prime factorization in exponent form.

Enter a number

Positive integers up to about 1,000,000,000,000 (10¹²).
Prime factorization
Number of factors
Sum of factors
All factors
Factor pairs

How to use this calculator

1. Type a positive whole number

Enter any integer from 1 upward. The tool handles values into the trillions, though very large numbers with no small factors take a moment to scan.

2. Read the factor list and count

Every divisor is listed in order, smallest to largest, with the total count beside it. The list is built by trial division up to the square root, so even big numbers stay fast.

3. Use the factor pairs

Each pair multiplies back to your number (for example 1 × 360, 2 × 180, …). Pairs are handy for factoring quadratics or splitting a quantity into equal groups.

4. Check the prime factorization

The prime breakdown is shown in exponent form, like 2³ × 3² × 5. This is the foundation for finding the greatest common factor or least common multiple of several numbers.

About factors

What is a factor of a number?

A factor is a whole number that divides another exactly, with no remainder. So 1, 2, 3, 4, 6 and 12 are all factors of 12. Every number has at least two factors — 1 and itself — and primes have exactly those two.

How does prime factorization relate?

Prime factorization breaks a number into a product of primes only, such as 360 = 2³ × 3² × 5. See the dedicated prime factorization calculator for a step-by-step factor tree.

Why count factors?

The factor count tells you how "divisible" a number is. Combined with prime factorization it powers the GCF & LCM calculator for working with several numbers at once.