83323...34849 (774-digits)

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

A 774-digit Proth prime of the form 1923*2^2560+1; with Proth witness a=11, 11^((N-1)/2) is congruent to -1 modulo N. [Balevsky]