Factors of 20
The factors of 20 are 1, 2, 4, 5, 10, and 20. In total, 20 has 6 factors. Its prime factorization is 2² × 5, and the sum of all its factors is 42.
All factors of 20
Here are all 6 factors of 20, listed from smallest to largest.
Factor pairs of 20
These 3 pairs of whole numbers each multiply to give 20.
Prime factorization of 20
Dividing 20 by the smallest prime at each step gives its prime factorization:
The distinct prime factors of 20 are 2, 5. To factorize any other number, use the prime factorization calculator.
Factor tree of 20
A factor tree shows the same prime factorization visually. Each composite branch splits until every endpoint is a prime number.
Properties of 20
| Number of factors | 6 |
|---|---|
| Sum of factors | 42 |
| Sum of proper factors | 22 |
| Prime factorization | 2² × 5 |
| Prime or composite? | Composite |
| Even or odd? | Even |
| Perfect square? | No |
| Perfect cube? | No |
| Classification | Abundant |
What makes 20 interesting
- 20 is a composite number, meaning it has more than two factors. It can be written as a product of smaller whole numbers in 3 different ways.
- 20 is an abundant number: its proper factors sum to 22, which is 2 more than 20 itself.
How to find the factors of 20 yourself
Divide 20 by each whole number starting from 1. Whenever the division leaves no remainder, both the divisor and the quotient are factors. You only need to test up to √20 ≈ 4.47, because every factor above that pairs with one below it.
Reading both columns gives every factor: 1, 2, 4, 5, 10, 20. The factor calculator does this automatically for any number.
Related numbers
Numbers mathematically connected to 20.
Frequently asked questions about 20
What are the factors of 20?
Is 20 a prime number?
What is the prime factorization of 20?
What two numbers multiply to give 20?
What is the sum of the factors of 20?
Is 20 a perfect square?
What is the largest factor of 20 other than itself?
How many factors does 20 have?
Explore more
Try another number in the factor calculator, break 20 down further with the prime factorization calculator, or compare 20 with another number using the GCF calculator and LCM calculator. For divisor counts and sums, see the divisor calculator.