On 2 October 2014, 3:02:44 UTC, PrimeGrid’s The Riesel Problem project eliminated k=402539 by finding the mega prime:
The prime is 2,159,301 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 20th overall. This is the largest prime found in The Riesel Problem and PrimeGrid's 13th elimination. 51 k's now remain.
The discovery was made by Walter Darimont (Walter Darimont) of Belgium using an Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz with 4 GB RAM running Linux. This computer took about 11 hours and 10 minutes to complete the primality test using LLR. Walter is a member of the Aggie the Pew Team.
The prime was verified on 2 October 2014, 9:51:42 UTC, by Tom Greer (tng*) of the United States using an Intel(R) Xeon(R) CPU E5520 @ 2.27GHz with 24 GB RAM running Microsoft Windows 7 Professional. This computer took about 25 hours and 35 minutes to complete the primality test using LLR. Tom is a member of the Sicituradastra. Team.
For more details, please see the official announcement.