Mathematicians at the University of Central Missouri have discovered a record-setting prime number that’s so large it would take about 6,000 pages of paper to print. The 22.3-million-digit discovery is the 49th known Mersenne prime number and the fourth discovered at the university. Primes are numbers such as 3, 7 and 11 that are divisible only by themselves and 1 without leaving a remainder. Mersenne primes are named after the 17th century French mathematician who discovered them, Marin Mersenne. They’re expressed as 2P-1, or 2 to the power of “P” minus 1. P is itself a prime number. For the new prime, P is 74,207,281.The number was independently verified, according to the Great Internet Mersenne Prime Search, a co-operative in which underused computing power is harnessed to perform the calculations needed to find and verify Mersenne primes.