Number Theory

Prime Factorization Calculator

Break down any composite number into its prime factors. View the results instantly in both expanded multiplication and condensed exponential forms.

Last updated: March 3, 2026

Handles huge numbers up to 15 digits
Formats into beautiful xⁿ Exponents
Automatically detects True Primes

What are Primes?

Primes are the "atoms" of mathematics. You can build every other single number by multiplying them together!

Prime Factorization
Decompose any integer into its prime building blocks.
Exponential Form
22×3×7
Repeated Multiplication Form
2 × 2 × 3 × 7

Building the Factor Tree

You can manually find the prime factorization of a number by drawing a factor tree. It involves successive division until you are left with nothing but prime numbers at the "leaves" of the tree.

Step 1: Divide by 2

Always start with the smallest prime number, which is 2. If the number is even, divide it by 2. Continue dividing the resulting quotients by 2 until you get an odd number.

For example, with the number 84:
84 ÷ 2 = 42
42 ÷ 2 = 21

Step 2: Ascend through Primes

Once the number is odd, you can no longer divide by 2. Move to the next prime, which is 3. Does 3 go in evenly? If yes, keep dividing by 3. Once 3 no longer works, move to 5, then 7, then 11, and so forth.

Continuing from 21:
21 ÷ 3 = 7
The number 7 is prime, so we stop! Our factors are 2, 2, 3, and 7.

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Prime Factorization Calculator | Find Prime Factors Tree