23232...32323 (359-digits)

This number is a prime.

                                                                   232323232
3232323232 3232323232 3232323232 3232323191 9191919191 9191919191 9191919191
9191917171 7171717171 7171717171 7171717171 3131313131 3131313131 3131311111
1111111111 1111111777 7777555553 3355555777 7777111111 1111111111 1111111313
1313131313 1313131313 1317171717 1717171717 1717171717 1717171919 1919191919
1919191919 1919191919 1919232323 2323232323 2323232323 2323232323 2323232323

The concatenation of 23 23's followed by 19 19's followed by 17 17's followed by 13 13's followed by 11 11's followed by 7 7's followed by 3 3's followed by 7 7's followed by 11 11's followed by 13 13's followed by 17 17's followed by 19 19's followed by 23 23's is prime. [Patterson]