Definition of a Prime number

Prime numbers are natural numbers greater than 1 that have no positive divisors other than 1 and themselves. In other words, a prime number is only divisible by 1 and itself. Some key points about prime numbers include:

1. First Few Prime Numbers: The first few prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, and so on.


2. 2 is Unique: It’s the only even prime number. All other even numbers are divisible by 2, so they cannot be prime.


3. Infinitude of Primes: There is an infinite number of prime numbers. This was proved by the ancient Greek mathematician Euclid.


4. Applications: Primes are crucial in number theory and have practical applications in fields like cryptography.



Prime numbers are also a building block in mathematics, as any integer greater than 1 can be factored into prime numbers in a unique way. This is called the Fundamental Theorem of Arithmetic.