What are the Factors of 21?
The factors of 21 are 1, 3, 7, 21 (total of 4 factors). Learn whether 21 is prime or composite and see all factor pairs.
Exact Answer
1, 3, 7, 21
Total Factors
4
Number Type
Composite Number
Smallest / Largest
1 and 21
Sum of Factors
32
Step-by-Step Solution: Factors(21) = 1, 3, 7, 21
Step 1
Find All Integers That Divide 21 Evenly
Test integers from 1 up to √21 (4.58). Every divisor with remainder 0 gives a factor pair of 21.
Factors of 21: 1, 3, 7, 21
Summary & Alternative Representations
| Property / Format | Value |
|---|---|
| Total Factors | 4 |
| Number Type | Composite Number |
| Smallest / Largest | 1 and 21 |
| Sum of Factors | 32 |
Was this solution helpful?
Help us improve our free step-by-step tools
Frequently Asked Questions
How many factors does 21 have?
21 has 4 positive factors: 1, 3, 7, 21.
Is 21 a prime number?
No, 21 is a composite number with 4 factors.