odd, composite, triangular · 91st positive integer
The number 91
91 is an odd composite number. It is the 91st positive integer.
Quick reference
| Prime factorization | 7 × 13 |
| Divisors | 1, 7, 13, 91 |
| Binary | 1011011 |
| Hexadecimal | 0x5B |
| Roman numeral | XCI |
| Digit sum | 10 |
| Properties | odd, composite, triangular |
Frequently asked
Is 91 a prime number?
No. 91 is composite. Its prime factorization is 7 × 13.
What are the factors of 91?
The factors (divisors) of 91 are 1, 7, 13, 91.
What is 91 in binary?
91 in binary is 1011011. In hexadecimal it's 5B.
What is 91 as a Roman numeral?
91 in Roman numerals is XCI.
What's the digit sum of 91?
Adding the digits of 91: 9 + 1 = 10.