Is 390 a prime number?
No, 390 is not a prime number. It is divisible by 2: 390 = 2 × 195.
Is 390 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 √390 ≈ 19.75. If none of them divides 390, it is prime.
- 3
2 divides 390 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 390 = 2 \times 3 \times 5 \times 13 \]
Testing 390 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 390 ÷ 2 | divides exactly (195) |
| 3 | 390 ÷ 3 | divides exactly (130) |
| 5 | 390 ÷ 5 | divides exactly (78) |
| 7 | 390 ÷ 7 | leaves 5 |
| 11 | 390 ÷ 11 | leaves 5 |
| 13 | 390 ÷ 13 | divides exactly (30) |
| 17 | 390 ÷ 17 | leaves 16 |
| 19 | 390 ÷ 19 | leaves 10 |
Questions
Is 390 a prime number?
No, 390 is not a prime number. It is divisible by 2: 390 = 2 × 195.
What is the next prime after 390?
397.
What is the prime number before 390?
389.
What are the factors of 390?
1, 2, 3, 5, 6, 10, 13, 15, 26, 30, 39, 65, 78, 130, 195, 390.