Cullen Prime Search



Cullen Primes are Cullen numbers that are prime and of the form Cn = n*2n+1. The are named after Reverend James Cullen who took interest in them back In 1905.

Cnis prime for n = 1, 141, 4713, 5795, 6611, 18496, 32292, 32469, 59656, 90825, 262419, 361275, 481899, 1354828, 6328548 and for no other n < 11,335,371

It is conjectured that there are infinitely many such primes. PrimeGrid has found the 2 largest Cullen primes:

6679881·26679881+1 : official announcement

6328548·26328548+1 : official announcement

For more information on Cullen numbers, please visit the following sites:


 * Cullen Prime - The Prime Glossary at the Prime Pages


 * Top 20 Cullen Primes - Top Twenty at the Prime Pages


 * Cullen Number - MathWorld--A Wolfram Web Resource


 * Cullen Number - Wikipedia