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!
1481โ1483, 1487โ1489, 1607โ1609 ...
1483โ1487, 1489โ1493, 1549โ1553, 1567โ1571, 1579โ1583, 1597โ1601, 1609โ1613 ...
1453โ1459, 1493โ1499, 1543โ1549, 1553โ1559, 1601โ1607 ...
Primes of the form 2โฟ - 1 less than 1543
Primes that read the same forwards and backwards
Primes that remain prime when digits are rotated (below 1543)
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