Is 315 a prime number?
No, 315 is not a prime number. It is divisible by 3: 315 = 3 × 105.
Is 315 prime?
Pick any whole number from 1 to 10,000.
How to work it out
- 1
A prime number has exactly two factors: 1 and itself.
- 2
It is enough to test the primes up to √315 ≈ 17.75. If none of them divides 315, it is prime.
- 3
3 divides 315 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 315 = 3^{2} \times 5 \times 7 \]Testing 315 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 315 ÷ 2 | leaves 1 |
| 3 | 315 ÷ 3 | divides exactly (105) |
| 5 | 315 ÷ 5 | divides exactly (63) |
| 7 | 315 ÷ 7 | divides exactly (45) |
| 11 | 315 ÷ 11 | leaves 7 |
| 13 | 315 ÷ 13 | leaves 3 |
| 17 | 315 ÷ 17 | leaves 9 |
Questions
Is 315 a prime number?
No, 315 is not a prime number. It is divisible by 3: 315 = 3 × 105.
What is the next prime after 315?
317.
What is the prime number before 315?
313.
What are the factors of 315?
1, 3, 5, 7, 9, 15, 21, 35, 45, 63, 105, 315.