Largest known repunit prime

The largest known is equal to R49,081 = (1049,081 − 1) / 9 which is 49,081 digits long; Harvey Dubner discovered it as a probable prime in 1999The Top Twenty: Repunit and its primality was proven in March 2022 by Paul Underwood.R(49081) - PrimePages (retrieved 2023-05-16)Paul Underwood's post at mersenneforum.org (retrieved 2023-01-10)
The largest known repunit probable prime is equal to R8,177,207 = (108,177,207 − 1) / 9 which is 8,177,207 digits long; it has been discovered on May 2021.Henri & Renaud Lifchitz's PRP Top - Search for : (10^?-1)/9 (retrieved 2021-06-05)
== Sources ==
Category:Numbers
Category:Class 2
Category:Numbers with 1000 to 1000000 digits
Category:Class 3
Category:Lower class 3
Category:Numerical records
Category:Prime numbers
Category:Probable primes
Category:Repdigit numbers
Category:Dynamic googolisms