What is a Prime Number?
A prime number is divisible only by 1 and itself. The first few primes are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29... Every integer greater than 1 is either prime or can be expressed as a product of primes (prime factorization).
48 = 2 x 2 x 2 x 2 x 3 = 2^4 x 3
100 = 2 x 2 x 5 x 5 = 2^2 x 5^2
Frequently Asked Questions
No. By definition, prime numbers must have exactly two distinct divisors: 1 and themselves. The number 1 has only one divisor (itself), so it is neither prime nor composite.
As of 2024, the largest known prime has over 41 million digits. It was discovered through the Great Internet Mersenne Prime Search (GIMPS). Mersenne primes have the form 2^p - 1 where p itself is prime.