Amateur sleuth finds largest known prime number with 41 million digits

After a six-year drought, we now have a new largest known prime number, thanks to an amateur mathematics sleuth who deployed an army of graphics processing units (GPUs) to crunch through the possibilities.

Prime numbers are those divisible only by 1 and themselves, such as 2, 3 and 5.  There are an infinite number of primes, but proving which numbers are actually prime becomes harder the larger they get. We can now add 2^136,279,841-1 to the list, which at 41,024,320 decimal digits long…