5 is the third prime number and the third single-digit prime. 5's prime factors are 1 and 5.
- Therefore it has 2 factors.
As an Exponent of Mersenne Number
25 - 1, which is the number 31, is a prime number. It is the 3rd Mersenne Prime.
Relationship with other numbers
The numbers before
- The previous odd number, 3, is a prime number.
- There are no odd numbers between 3 and 5. As a result, they are twin primes.
- 2 is the first prime number. It is the only even prime number.
- 1, the number before 2, is not a prime number.
The numbers after
- The next odd number, 7, is a prime number.
- There are no odd numbers between 5 and 7. As a result, they are twin primes.
- 9, the odd number following 7, is a square number. It is the first odd composite number.
- 11, the odd number following 9, is a prime number.
- 5 and 11 are six numbers apart, therefore, they are sexy primes.
- 5 is the only number that is part of two twin prime pairs, (3, 5) and (5, 7).