The biggest ever prime number so far has been calculated by the Great Mersenne Prime Search (GIMPS), New Scientist, Yahoo News and others reported Feb. 5, 2013. The new prime number, two to the power of 57,885,161, minus one, has 17,425,170 digits.
While the prime was discovered on Jan. 25, 2013, it had to be independently verified on several computers before anyone cracked out the champagne. The new prime number beats the previous record of 12,978,189 digits from 2008.
Using a network of around 360,000 volunteer computers that run the calculations in the background — a bit like SETI, the extraterrestrial life project — the new mega-prime number was calculated on volunteer Dr. Curtis Cooper's team machine at the University of Central Missouri. Those who discover big new primes receive grant money prizes for research.
The new prime is part of a special class of prime number, Mersenne Primes, which take the form of two to the power of something, minus one. However, the “something” also has to be a prime. According to the University of Tennessee at Martin's Mersenne Prime page, they are named for a 16th and 17th-century French monk, Marin Mersennes, who studied them.
It is only the 48th Mersenne prime ever found. Team Cooper should probably buy a lottery ticket; it had previously discovered two more record primes, in 2005 and 2006.
GIMPS has been merrily calculating primes in the background since 1996. According to the GIMPS website, volunteers download the software and become part of“grassroots supercomputing” — the Borg of primes, perhaps.
A prime number is one that cannot be divided by anything other than itself, and 1. Examples that do not make the mind fold in on itself include 3, 5, 7, 11 and 13.
The Great Mersenne Prime Search program has been used by math teachers to get kids excited about math, since they can download the software on their own machines and take part in something much, much larger.
What's next? GIMPS is looking for the first million-digit prime number. If it does, it stands to win a $150,000 research grant from the The Electronic Frontier Foundation. The first billion-digit prime gets a cool quart-million dollars. Now that would be a prime objective.