10801...80199 (91-digits)

This number is a prime.

                                                     1 0801991081 6991086091
1086101108 6119108661 1108668910 8661110861 1910861011 0860911081 6991080199

The smallest prime formed from the concatenation of n consecutive n-digit invertible primes in the pattern {a, b, c, d, e, f, g, f, e, d, c, b, a}, i.e., {1080199, 1081699, 1086091, 1086101, 1086119, 1086611, 1086689, 1086611, 1086119, 1086101, 1086091, 1081699, 1080199}, (case n=7). [Bajpai]