Samuel Yates began, and this site continues, a database of the largest known primes. Primes in that database are assigned a proof-code to show who should be credited with the discovery as well as what programs and projects they used. (Discoverers have one prover-entry, but may have many proof-codes because they use a variety of programs...)
This page provides data on L3421, one of those codes.
Code name (*): L3421 Persons (*): 1 (counting humans only) Projects (*): 1 (counting projects only) Display (HTML): Handa, TwinGen, PrimeGrid, LLR Number of primes: total 1 Unverified Primes: 0 (prime table entries marked 'Composite','Untested', or 'InProcess' Score for Primes (*): total 43.7287
Below is additional information about this entry.
Display (text): Handa, TwinGen, PrimeGrid, LLR Display (short): Handa Database id: 7073 (do not use this database id, it is subject to change) Proof program: LLR Entry last modified: 2022-06-24 17:50:37