No, 305 is not a prime number. It is a composite number: it ends in 5, so it is divisible by 5.
305 has divisors other than 1 and itself. The smallest is 5: 305 ÷ 5 = 61.
Prime factorization: 305 = 5 × 61.
| Number | Prime? |
|---|---|
| 301 | No, 7 × 43 |
| 302 | No, 2 × 151 |
| 303 | No, 3 × 101 |
| 304 | No, 2 × 2 × 2 × 2 × 19 |
| 306 | No, 2 × 3 × 3 × 17 |
| 307 | Yes |
| 308 | No, 2 × 2 × 7 × 11 |
| 309 | No, 3 × 103 |
Another number? Use the prime number checker for any value, or see the list of prime numbers.