odd, composite, perfect square · 25th positive integer
The number 25
25 is an odd composite number. It's known as the perfect square of 5. It is the 25th positive integer.
Quick reference
| Prime factorization | 5 × 5 |
| Divisors | 1, 5, 25 |
| Binary | 11001 |
| Hexadecimal | 0x19 |
| Roman numeral | XXV |
| Digit sum | 7 |
| Properties | odd, composite, perfect square |
Why 25 is notable
The perfect square of 5.
Reading 25 in NumGrid context
25 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.
Every number on this page links back to classical number theory plus NumGrid solver-derived puzzle statistics; the methodology page describes the inputs, refresh cadence, and known limitations of the underlying data product.
Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for 25’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 25 a prime number?
No. 25 is composite. Its prime factorization is 5 × 5.
What are the factors of 25?
The factors (divisors) of 25 are 1, 5, 25.
What is 25 in binary?
25 in binary is 11001. In hexadecimal it's 19.
What is 25 as a Roman numeral?
25 in Roman numerals is XXV.
What's the digit sum of 25?
Adding the digits of 25: 2 + 5 = 7.