even, composite · 72nd positive integer
The number 72
72 is an even composite number. It's known as the rule-of-72 number used to estimate doubling time at compound interest. It is the 72nd positive integer.
Quick reference
| Prime factorization | 2 × 2 × 2 × 3 × 3 |
| Divisors | 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72 |
| Binary | 1001000 |
| Hexadecimal | 0x48 |
| Roman numeral | LXXII |
| Digit sum | 9 |
| Properties | even, composite |
Why 72 is notable
The rule-of-72 number used to estimate doubling time at compound interest.
Frequently asked
Is 72 a prime number?
No. 72 is composite. Its prime factorization is 2 × 2 × 2 × 3 × 3.
What are the factors of 72?
The factors (divisors) of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72.
What is 72 in binary?
72 in binary is 1001000. In hexadecimal it's 48.
What is 72 as a Roman numeral?
72 in Roman numerals is LXXII.
What's the digit sum of 72?
Adding the digits of 72: 7 + 2 = 9.