A little clarity. A lot more confidence. Explore exam dates & family resources →

What Are Factors? Learn How to Find Them Quickly

Recovered historical Refresh Kid article. Original dates and context are retained; this version awaits editorial review.

What Are Factors?

Factors are numbers you can multiply together to get another number. If a number can be divided evenly by another number, that number is a factor.
[caption id="attachment_657" align="alignleft" width="300"]An educational graphic showing the multiplication equation 2 × 4 = 8, with arrows pointing from 2 and 4 labeled "Factors" and from 8 labeled "Product." The design uses Refresh Kid LLC's brand colors—white text and orange arrows on a deep blue background Understanding Multiplication[/caption] Example:
  • Factors of 12 are 1, 2, 3, 4, 6, and 12 because:
    • 1 × 12 = 12
    • 2 × 6 = 12
    • 3 × 4 = 12

How to Find Factors of a Number

Step 1: Start with 1 and the Number Itself

Every number has 1 and itself as factors.

Step 2: Check for Divisibility

Divide the number by smaller numbers starting from 2. If there’s no remainder, the divisor is a factor.

Step 3: Continue Checking

Keep checking divisibility until you reach the number’s square root. Example Table:
Number Factors
15 1, 3, 5, 15
24 1, 2, 3, 4, 6, 8, 12, 24
36 1, 2, 3, 4, 6, 9, 12, 18, 36

Examples and Solutions

Example 1: Find Factors of 18

  • Divide 18 by 1, 2, 3, 6, 9, and 18.
  • Factors of 18: 1, 2, 3, 6, 9, 18

Example 2: Find Factors of 20

  • Divide 20 by 1, 2, 4, 5, 10, and 20.
  • Factors of 20: 1, 2, 4, 5, 10, 20

Example 3: Find Factors of 28

  • Divide 28 by 1, 2, 4, 7, 14, and 28.
  • Factors of 28: 1, 2, 4, 7, 14, 28

Types of Factors

1. Prime Factors

  • Factors that are prime numbers (numbers greater than 1 that only have 1 and themselves as factors).
  • Example: Prime factors of 18 are 2 and 3, because:
    • 18 = 2 × 3 × 3 (prime factorization)

2. Common Factors

  • Factors that two or more numbers have in common.
  • Example: Common factors of 12 and 18 are 1, 2, 3, and 6.

3. Greatest Common Factor (GCF)

  • The largest factor that two or more numbers share.
  • Example: GCF of 24 and 36 is 12 because 12 is the biggest number that evenly divides both 24 and 36.

4. Composite Factors

  • Factors that are not prime numbers (they have more than two factors).
  • Example: In factors of 18 (1, 2, 3, 6, 9, 18), numbers like 6, 9, and 18 are composite.

5. Unique Factors

  • Factors that are only counted once in factor lists.
  • Example: Even though 3 appears multiple times in the prime factorization of 18, it is counted only once as a unique factor.

Why Are Factors Important?

Factors help with:
  • Simplifying fractions
  • Solving equations
  • Finding multiples and divisors

Quick Tips to Remember Factors

  • Even Numbers: Always have 2 as a factor.
  • Odd Numbers: Never have 2 as a factor.
  • Zero: Every number is a factor of 0.
  • One: Is a factor of every number.

Practice With Refresh Kid

Want to practice more?
We make math fun and easy at Refresh Kid LLC!

Check out:

One-on-one support
Built around your student
Let’s talk →