No, 428 is not a prime number. It is a composite number: it is even, so it is divisible by 2.
428 has divisors other than 1 and itself. The smallest is 2: 428 ÷ 2 = 214.
Prime factorization: 428 = 2 × 2 × 107 = 2² × 107.
| Number | Prime? |
|---|---|
| 424 | No, 2 × 2 × 2 × 53 |
| 425 | No, 5 × 5 × 17 |
| 426 | No, 2 × 3 × 71 |
| 427 | No, 7 × 61 |
| 429 | No, 3 × 11 × 13 |
| 430 | No, 2 × 5 × 43 |
| 431 | Yes |
| 432 | No, 2 × 2 × 2 × 2 × 3 × 3 × 3 |
Another number? Use the prime number checker for any value, or see the list of prime numbers.