16225...88127 (33-digits)

This number is a prime.

                                        162 2592768292 1336339157 8010288127

In 1914, R. E. Powers announced that he had found M(107) to be prime and almost immediately E. Fauquembergue announced he also had discovered this fact. Note that 1914 was the start of WWI!

The second Mersenne prime that is a full period prime [Ewing]