11757...75711 (91-digits)

This number is a prime.

                                                     1 1757111177 7111178711
1180811118 3811118681 1119091111 8681111838 1111808111 1787111177 7111175711

The smallest palindromic prime formed from the concatenation of n consecutive n-digit palindromic primes in the pattern {a, b, c, d, e, f, g, f, e, d, c, b, a}, i.e., {1175711, 1177711, 1178711, 1180811, 1183811, 1186811, 1190911, 1186811, 1183811, 1180811, 1178711, 1177711, 1175711}, (case n=7). [Bajpai]