Largest prime number

Good news for number theory enthusiasts. Two new larger prime numbers are discovered.
These are 2^37,156,667-1, and 2^43,112,609-1.Previousely the known largest prime was 2^110,503-1 discovered in 1988.
These are mersenne primes(primes which can be expressed as one minus a power of 2). Mersenne primes are very rare and till now only 46 numbers are discovered. For more details
see the GIMPS(Great Internet Mersenne Prime Search) home page.GIMPS is a is a collaborative project of volunteers who use Prime95 and Mprime software that can be downloaded from for free from net to search for mersenne primes.
References
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