odd, prime · 643rd positive integer
The number 643
643 is an odd prime number. It is the 643rd positive integer.
Quick reference
| Prime factorization | 643 (prime) |
| Divisors | 1, 643 |
| Binary | 1010000011 |
| Hexadecimal | 0x283 |
| Roman numeral | DCXLIII |
| Digit sum | 13 |
| Properties | odd, prime |
Frequently asked
Is 643 a prime number?
Yes. 643 is prime — its only divisors are 1 and itself.
What are the factors of 643?
The factors (divisors) of 643 are 1, 643.
What is 643 in binary?
643 in binary is 1010000011. In hexadecimal it's 283.
What is 643 as a Roman numeral?
643 in Roman numerals is DCXLIII.
What's the digit sum of 643?
Adding the digits of 643: 6 + 4 + 3 = 13.