Prime Number Checker
Check if a number is prime
A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.
Prime factorization breaks down a number into its prime number components.
Generate a list of prime numbers within a specified range or find the first N prime numbers.
Twin primes are pairs of prime numbers that differ by 2 (e.g., 3,5 or 11,13 or 17,19).
Prime Number Reference
First 20 Prime Numbers
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71
Prime Number Facts
- • 2 is the only even prime number
- • 1 is not considered a prime number
- • There are infinitely many prime numbers
Twin Prime Pairs (up to 100)
(3,5), (5,7), (11,13), (17,19), (29,31), (41,43), (59,61), (71,73)
Testing Methods
- • Trial Division: Test divisibility up to √n
- • Sieve of Eratosthenes: Efficient for ranges
- • Optimized: Skip even numbers after 2