Is 25 a prime number?
No, 25 is not a prime number. It is divisible by 5: 25 = 5 × 5.
Is 25 prime?
Pick any whole number from 1 to 10,000.
How to work it out
- 1
A prime number has exactly two factors: 1 and itself.
- 2
It is enough to test the primes up to √25 ≈ 5.00. If none of them divides 25, it is prime.
- 3
5 divides 25 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 25 = 5^{2} \]Testing 25 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 25 ÷ 2 | leaves 1 |
| 3 | 25 ÷ 3 | leaves 1 |
| 5 | 25 ÷ 5 | divides exactly (5) |
Questions
Is 25 a prime number?
No, 25 is not a prime number. It is divisible by 5: 25 = 5 × 5.
What is the next prime after 25?
29.
What is the prime number before 25?
23.
What are the factors of 25?
1, 5, 25.