Factors of 640
The factors of 640 are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640. It has 16 factors.
Pick any whole number from 1 to 10,000.
How to work it out
- 1
A factor of 640 is a whole number that divides it with nothing left over. You only need to test the numbers up to ā640 ā 25.30; every one that divides gives a pair.
- 2
The factor pairs are listed in the table below. Together they give 16 factors.
- 3
Prime factorisation: keep dividing by the smallest prime that fits.
- 4
Add all the factors: the sum is 1530. Without 640 itself that is 890, so 640 is an abundant number.
LaTeX source of the formulas on this page
\[ 640 = 2^{7} \times 5 \]Factor pairs of 640
| Factor | Pairs with | Product |
|---|---|---|
| 1 | 640 | 1 Ć 640 = 640 |
| 2 | 320 | 2 Ć 320 = 640 |
| 4 | 160 | 4 Ć 160 = 640 |
| 5 | 128 | 5 Ć 128 = 640 |
| 8 | 80 | 8 Ć 80 = 640 |
| 10 | 64 | 10 Ć 64 = 640 |
| 16 | 40 | 16 Ć 40 = 640 |
| 20 | 32 | 20 Ć 32 = 640 |
Questions
What are the factors of 640?
The factors of 640 are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640. It has 16 factors.
What are the prime factors of 640?
2, 5. As a product: Ć 5.
How many factors does 640 have?
640 has 16 factors (8 factor pairs).
What is the sum of the factors of 640?
1530.
Is 640 a prime number?
No. It is divisible by 2, so 640 = 2 Ć 320.