On 5 October 2013, 19:06:07 UTC, PrimeGrid’s The Riesel Problem project eliminated k=398023 by finding the mega prime:
The prime is 1,932,034 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 23rd overall. This is the largest prime found in The Riesel Problem and PrimeGrid's 10th elimination. 54 k's now remain.
The discovery was made by Vladimir Volynsky (Grey) of Russia using an Intel(R) Core(TM) i7- 3820 CPU @ 3.60GHz with 16 GB RAM running Windows 7 x64. This computer took 12 hours 43 minutes to complete the primality test using LLR. Vladimir is a member of the Russia team.
The prime was verified on 8 October 2013, 00:48:18 UTC, by Wolfgang Schwieger (DeleteNull) of Germany using an Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz with 16 GB RAM running Linux. This computer took 10 hours 4 minutes to complete the primality test using LLR. Wolfgang is a member of the Nemesis Germany team.
For more details, please see the official announcement.