99198...47337 (300-digits)

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

                                                       9919839779 7196795394
7941937929 9199119078 8788388187 7863859857 8538398298 2782382181 1809797787
7737697617 5775174373 9733727719 7097016916 8367767366 1659653647 6436416316
1961761360 7601599593 5875775715 6956355754 7541523521 5095034994 9148747946
7463461457 4494434394 3343142141 9409401397 3893833793 7336735935 3349347337

The smallest prime formed from the reverse concatenation of one hundred consecutive primes. [Bajpai]