A prime number discovered on December 26, 2017, has 23,249,425 digits. When it was announced in January 2018, it was only the 50th Mersenne prime ever found.
ILLUSTRATION · AIThe number M77232917, discovered in December 2017, has 23,249,425 digits and was the 50th Mersenne prime known when it was announced in January 2018.
A Mersenne prime is a prime number of the form 2 raised to a power, minus 1. On December 26, 2017, a computer volunteered by Jonathan Pace of Germantown, Tennessee, found one: 2^77,232,917 − 1, a number with 23,249,425 digits.
The Great Internet Mersenne Prime Search, or GIMPS, announced it on January 3, 2018, as M77232917, the 50th known Mersenne prime and at that time the largest known prime number.
Checked more than once
Before an announcement, GIMPS has a new prime verified independently. Other volunteers confirmed this one with separate software and hardware, including runs on a 32-core server and on a cloud computing instance.
Pace, a 51-year-old electrical engineer, had been hunting for big primes with GIMPS for over 14 years. The primes carry the name of Marin Mersenne, a French Minim friar born in 1588 who studied numbers of this form.
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