Discover if your number is Prime or Composite โ fast and easy!
โ Yes! It's a Prime Number
Prime numbers are only divisible by 1 and itself.
Explore comprehensive data about prime numbers and their fascinating properties.
Click any prime to analyze it!
4481โ4483, 4517โ4519, 4547โ4549, 4637โ4639, 4649โ4651 ...
4513โ4517, 4519โ4523, 4639โ4643 ...
4457โ4463, 4507โ4513, 4561โ4567, 4591โ4597, 4597โ4603, 4643โ4649, 4651โ4657 ...
Primes of the form 2โฟ - 1 less than 4561
Primes that read the same forwards and backwards
Primes that remain prime when digits are rotated (below 4561)
Prime numbers are the building blocks of mathematics, encryption, and more. Explore what makes them fascinating.
A prime number is a natural number greater than 1 that has no positive divisors other than 1
and itself.
Prime numbers cannot be formed by multiplying two smaller natural numbers. The first few are:
2, 3, 5, 7, 11, 13, 17, 19, 23...
ฯ(n) โ n/ln(n) - The density of primes decreases logarithmically
ฮถ(s) = 0 only at s = -2,-4,-6... and Re(s) = 1/2
For n > 1, there's always a prime between n and 2n
Test divisibility up to โn - Simple but slow O(โn)
Probabilistic test - Fast O(k logยณ n) with k rounds