12345...68789 (167-digits)

This number is a prime.

                                               1234567 8910111213 1415161718
1920212223 2425262728 2930313233 3435363738 3940414243 4445464748 4950515253
5455565758 5960616263 6465666768 6970717273 7475767778 7980818283 8485868789

A prime formed by concatenating the numbers 1 to 88, then adding 1. [Wesolowski]