Yes, 479 is a prime number. Its only factors are 1 and 479.
A number is prime if no smaller prime up to its square root divides it. The square root of 479 is about 21.89, so it is enough to test the primes 2, 3, 5, 7, 11, 13, 17 and 19.
| Divide by | Remainder | Divides evenly? |
|---|---|---|
| 2 | 1 | No |
| 3 | 2 | No |
| 5 | 4 | No |
| 7 | 3 | No |
| 11 | 6 | No |
| 13 | 11 | No |
| 17 | 3 | No |
| 19 | 4 | No |
None of them divides 479 evenly, so 479 is prime.
| Number | Prime? |
|---|---|
| 475 | No, 5 × 5 × 19 |
| 476 | No, 2 × 2 × 7 × 17 |
| 477 | No, 3 × 3 × 53 |
| 478 | No, 2 × 239 |
| 480 | No, 2 × 2 × 2 × 2 × 2 × 3 × 5 |
| 481 | No, 13 × 37 |
| 482 | No, 2 × 241 |
| 483 | No, 3 × 7 × 23 |
Another number? Use the prime number checker for any value, or see the list of prime numbers.