93929...42221 (114-digits)

This number is a prime.

                            9392 9190888786 8584828180 7877767574 7270696866
6564636260 5857565554 5251504948 4645444240 3938363534 3332302827 2625242221

The largest prime formed by reverse concatenation of n consecutive double-digit composite numbers (n = 57). [Gupta]