11110...11111 (241-digits)

This number is a probable-prime (likely to be a prime but we have not (re-)proven it on this site).

                                          1 1110998888 7888900111 1100000000
0000111109 9888878889 0011222109 9888878890 1122110999 8887788901 1111109998
7889011222 2210987766 6779011222 2210988879 0001111110 9888778890 0011122109
8887888900 1122210998 8887888900 1111100000 0000000111 1099888878 8890011111

The only non-titanic beastly unique prime. [Marcel]