๐ Factor Calculator Online
Find all factors, prime factorization, factor pairs, GCF & LCM of any number — instantly and for free.
What Is a Factor Calculator?
A Factor Calculator is a free online math tool that finds all the factors (divisors) of any whole number you enter. Instead of manually dividing a number by every possible integer, our calculator does it in milliseconds — showing you:
- All factors of the number
- Prime factorization (with exponents)
- All factor pairs
- Whether the number is prime or composite
- Total number of divisors
- GCF (Greatest Common Factor) and LCM (Least Common Multiple) with any second number
What Are Factors of a Number?
A factor of a number is any integer that divides the number exactly (with no remainder). For example, the factors of 12 are 1, 2, 3, 4, 6, and 12 — because each of these divides 12 evenly.
Prime Factorization of 36 → 2² × 3²
Factor Pairs of 36 → (1×36), (2×18), (3×12), (4×9), (6×6)
How to Find Factors of a Number – Step by Step
- Start from 1 and go up to the square root of the number.
- For each integer i, check if it divides the number with zero remainder.
- If yes, both i and n ÷ i are factors.
- Collect all such values in sorted order — those are all the factors.
Our Factor Calculator automates every step of this process instantly.
Prime Factorization Explained
Prime factorization breaks a number down into a product of its prime factors. Every composite number has a unique prime factorization (by the Fundamental Theorem of Arithmetic).
360 ÷ 2 = 180 → 180 ÷ 2 = 90 → 90 ÷ 2 = 45 → 45 ÷ 3 = 15 → 15 ÷ 3 = 5 → 5 ÷ 5 = 1
∴ 360 = 2³ × 3² × 5
Factor Pairs
A factor pair is a set of two numbers that multiply together to give the original number. For every factor less than or equal to the square root, there is a corresponding larger factor that pairs with it.
For 60: factor pairs are (1, 60), (2, 30), (3, 20), (4, 15), (5, 12), (6, 10).
What Is GCF (Greatest Common Factor)?
The GCF, also called HCF (Highest Common Factor), is the largest number that divides two or more numbers exactly. It is used to simplify fractions and solve problems involving equal groups or sharing.
GCF of 24 and 36 → Factors of 24: 1,2,3,4,6,8,12,24 | Factors of 36: 1,2,3,4,6,9,12,18,36 → GCF = 12
What Is LCM (Least Common Multiple)?
The LCM is the smallest positive integer that is divisible by two or more numbers. It is widely used in adding fractions with different denominators and scheduling problems.
Formula: LCM(a, b) = (a × b) ÷ GCF(a, b)
LCM of 4 and 6 → GCF = 2, so LCM = (4×6)÷2 = 12
Is 1 a Factor of Every Number?
Yes. 1 divides every whole number evenly, so 1 is always a factor of any positive integer. Similarly, every number is a factor of itself.
Common Uses of Factoring in Real Life
- Simplifying fractions: Divide numerator and denominator by their GCF.
- Tiling & arrangements: Determine how to arrange items in equal rows/columns.
- Cryptography: Large prime factorization underlies RSA encryption.
- Algebra: Factor polynomials and quadratic equations.
- Scheduling: Find common time intervals using LCM.
Frequently Asked Questions
Factor Table: Quick Reference
| Number | All Factors | Count | Prime? |