About Prime Numbers
A prime number is a natural number greater than 1 that is only divisible by 1 and itself.
In other words, it has exactly two factors: 1 and the number itself.
Examples:
- 2 is prime (the smallest and only even prime number)
- 3 is prime (factors: 1, 3)
- 4 is not prime (factors: 1, 2, 4)
- 5 is prime (factors: 1, 5)
- 6 is not prime (factors: 1, 2, 3, 6)
Properties:
- There are infinitely many prime numbers
- Every integer greater than 1 can be uniquely factored into prime numbers
- 2 is the only even prime number
- 1 is not considered prime by definition
Applications:
- Cryptography (RSA encryption)
- Hash functions
- Number theory
- Computer science algorithms