prime numbers

In 1874, an English mathematician W. Stanley Jevons claimed that only he knew the divisors of the prime number 8, 616, 460,799. He had obtained this number by multiplying two of the largest prime numbers known then viz., 96079 and 89681.The largest prime number discovered without the help of computers consisted of 39 digits it reigned supreme from 1876 to the middle of the 20th century. With the help of computers the quest for the largest prime number surged forward.In 1983, the largest known prime number was a monster with 39,000 digits in it. In 1986, the largest known prime number has an astounding 60,000 digits in it. It will occupy more than 500 lines and require 25 pages to be written down.New and sophisticated methods have been evolved to determine whether or not a number is a prime. No longer need we use the old method of successive divisions to check for remainders. In this method, even the super computer of today would not have time to explore a number with a mere 50-digits, even if it had worked non-stop for 15 billion years.Josh Findley, a volunteer in the Mersenne.org research project called the Great Internet Mersenne Prime Search (GIMPS), has discovered the largest known prime number. Findley used his home PC and free software by George Woltman and Scott Kurowski as part of an international grid of 240,000 networked computers in virtually every time zone of the world.The new number, expressed as 2 to the 24,036,583th power minus 1, has 7,235,733 decimal digits and was discovered May 15th. It is nearly a million digits larger than the previous largest known prime number, and belongs to a special class of rare prime numbers called Mersenne primes . The discovery marks only the 41st known Mersenne prime, named after Marin Mersenne , a 17th century French monk who first studied the rare numbers 300 years ago. Mersenne primes are most relevant to number theory, but most participants join GIMPS simply for the fun of having a role in real research - and the chance of finding a new Mersenne prime.