Factors of 21
The factors of 21 are 1, 3, 7, 21. No, 21 is a composite number. Its prime factorization is 3 × 7.
Factors of 21
1, 3, 7, 21
Prime or Composite
Composite
Perfect Square
No
Prime Factorization
3 × 7
Sum of Factors
32
| Factor Pairs |
|---|
| 1 × 21 = 21 |
| 3 × 7 = 21 |
Frequently Asked Questions
What are the factors of 21?
The factors of 21 are 1, 3, 7, 21.
Is 21 a prime number?
No, 21 is a composite number. Its prime factorization is 3 × 7.
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