No, 72 is not a prime number. It is a composite number: it is even, so it is divisible by 2.
72 has divisors other than 1 and itself. The smallest is 2: 72 ÷ 2 = 36.
Prime factorization: 72 = 2 × 2 × 2 × 3 × 3 = 2³ × 3².
| Number | Prime? |
|---|---|
| 68 | No, 2 × 2 × 17 |
| 69 | No, 3 × 23 |
| 70 | No, 2 × 5 × 7 |
| 71 | Yes |
| 73 | Yes |
| 74 | No, 2 × 37 |
| 75 | No, 3 × 5 × 5 |
| 76 | No, 2 × 2 × 19 |
More about 72: factors of 72 · 72 squared · square root of 72 · 72 in binary · 72 in Roman numerals.
Another number? Use the prime number checker for any value, or see the list of prime numbers.