On 16 November 2017, 15:38:45 UTC, PrimeGrid’s Generalized Fermat Prime Search found the Generalized Fermat mega prime:
The prime is 1,718,572 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 6th for Generalized Fermat primes and 53rd overall.
The discovery was made by Howard Gordon ([PST]Howard) of the United Kingdom using a Nvidia GeForce GTX 1060 in an AMD Ryzen 1950X with 32GB RAM, running Microsoft Windows 10 Core Edition. This GPU took about 30 minutes to probable prime (PRP) test with GeneferOCL3. Howard is a member of the PrimeSearchTeam team.
The prime was verified on 30 November 2017, 01:04:13 UTC, by user Brian Uitti of the United States using an Intel(R) Core(TM) i5 M 520 CPU @ 2.4GHz with 4GB RAM, running Linux. This CPU took about 3 days, 12 hours, 6 minutes to probable prime (PRP) test with Genefer. Brian is a member of the Project Blue Book team.
The PRP was confirmed prime by an Intel(R) Core(TM) i5-4670K CPU @ 3.40GHz with 24GB RAM, running Microsoft Windows 7 Professional Edition. This computer took about 10 hours 10 minutes to complete the primality test using multithreaded LLR.
For more details, please see the official announcement.