90909...09091 (30-digits)

This number is a prime.

                                            9090909090 9090909090 9090909091

+ Fourth prime of the form (10^P + 1)/11, where P is prime. The first seven primes of this form are for P = 5, 7, 19, 31, 53, 67 and 293. [Matson]

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