No, 90 is not a prime number. It is a composite number: it is even, so it is divisible by 2.
90 has divisors other than 1 and itself. The smallest is 2: 90 ÷ 2 = 45.
Prime factorization: 90 = 2 × 3 × 3 × 5 = 2 × 3² × 5.
| Number | Prime? |
|---|---|
| 86 | No, 2 × 43 |
| 87 | No, 3 × 29 |
| 88 | No, 2 × 2 × 2 × 11 |
| 89 | Yes |
| 91 | No, 7 × 13 |
| 92 | No, 2 × 2 × 23 |
| 93 | No, 3 × 31 |
| 94 | No, 2 × 47 |
More about 90: factors of 90 · 90 squared · square root of 90 · 90 in binary · 90 in Roman numerals.
Another number? Use the prime number checker for any value, or see the list of prime numbers.