Factors of 100
There are 9 factors of 100 — the full list is below, with factor pairs, prime factorization, and divisibility notes.
Factors of 100
1, 2, 4, 5, 10, 20, 25, 50, 100
Factor pairs of 100
- 1 × 100
- 2 × 50
- 4 × 25
- 5 × 20
- 10 × 10
Prime factorization of 100
100 = 2² × 5²
Number facts
- 100 is a composite number.
- 100 has 9 factors.
- 100 is a perfect square.
- The sum of all factors of 100 is 217.
Divisibility rules that apply to 100
- 100 is divisible by 2 because it ends in an even digit (0, 2, 4, 6, or 8).
- 100 is divisible by 5 because it ends in 0 or 5.
- 100 is divisible by 10 because it ends in 0.
Check another number
How the factors of 100 are calculated
To find the factors of 100, every whole number from 1 up to the square root of 100(about 10.00) is tested for even division. 100 is even, and it divides evenly by 2, 4, 5, 10, among others. Written as a product of primes, 100 = 2² × 5², which confirms every factor above is a combination of those prime building blocks. 100 is also a perfect square, which is why one of its factor pairs is a number multiplied by itself.
Frequently asked questions about 100
How many factors does 100 have?
100 has 9 factors: 1, 2, 4, 5, 10, 20, 25, 50, 100.
Is 100 a prime number?
No. 100 is composite because it has factors other than 1 and itself.
What are the factor pairs of 100?
The factor pairs of 100 are 1 × 100, 2 × 50, 4 × 25, 5 × 20, 10 × 10.
What is the prime factorization of 100?
The prime factorization of 100 is 2² × 5².