odd, prime · 809th positive integer
The number 809
809 is an odd prime number. It is the 809th positive integer.
Quick reference
| Prime factorization | 809 (prime) |
| Divisors | 1, 809 |
| Binary | 1100101001 |
| Hexadecimal | 0x329 |
| Roman numeral | DCCCIX |
| Digit sum | 17 |
| Properties | odd, prime |
Reading 809 in NumGrid context
809 is one of the data points covered by this site’s integer properties and number-guessing puzzles dataset. The detail above comes directly from classical number theory plus NumGrid solver-derived puzzle statistics; the context that follows situates the headline numbers against the broader distribution across positive integers within the NumGrid target pool.
The methodology behind every numeric value on this page is publicly documented on the classical number theory plus NumGrid solver-derived puzzle statistics portal and described in detail on this site’s methodology page. Refresh cadence varies by underlying series; the page surfaces the as-of date for each number so readers can trace any figure back to the source release.
Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for 809’s peers within positive integers within the NumGrid target pool. A single-entity reading without peer context can be misleading when an entity is an outlier on one axis but typical on another.
Frequently asked
Is 809 a prime number?
Yes. 809 is prime — its only divisors are 1 and itself.
What are the factors of 809?
The factors (divisors) of 809 are 1, 809.
What is 809 in binary?
809 in binary is 1100101001. In hexadecimal it's 329.
What is 809 as a Roman numeral?
809 in Roman numerals is DCCCIX.
What's the digit sum of 809?
Adding the digits of 809: 8 + 0 + 9 = 17.