1163

This number is a prime.

Consider a n-by-n Ulam spiral of digits from the decimal expansion of π. The sequence generated for the maximum number of distinct primes in the standard number search format (i.e., forward/backward along rows, columns, and diagonals) begins 1, 6, 16, 34, 44, ... (G. L. Honaker, Jr., 3/14/15 9:26:53.589...)

                                       5 1 4
*Note that in the 3-by-3 square, i.e., 9 3 1 , the sum of 16 distinct primes equals 1163.
                                       2 6 5