On 12 March 2020, 19:16:51 UTC, PrimeGrid’s Sierpinski/Riesel Base 5 Problem project eliminated k=238694 by finding the mega prime:
The prime is 2,082,532 digits long and enters Chris Caldwell's “The Largest Known Primes Database” ranked 76th overall and is the largest known base 5 prime. 64 k’s now remain in the Riesel Base 5 problem.
The discovery was made by Chris Howell (Khali) of the United States using an Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz with 32GB RAM, running Microsoft Windows 10 Professional x64 Edition. This computer took about 5 hours, 56 minutes to complete the primality test using LLR. Chris Howell is a member of the Crunching@EVGA team.
The prime was verified on 13 March 2020, 21:25:52 UTC by Yuki Yoshigoe (SAKAGE@AMD@jisaku) of Japan using an AMD Ryzen Threadripper 3970X 32-Core Processor with 128GB RAM, running Microsoft Windows 10 Professional x64 Edition. This computer took about 1 day, 5 hours, 24 minutes to complete the primality test using LLR. Yuki Yoshigoe is a member of the Team 2ch team.
For more details, please see the official announcement.