This number is a prime.

                                                              999 9999998987

+ The largest example with the smallest emirp number of digits (13) of an emirp with an emirp sum of digits. 9999999998987 is prime; its reversal 7898999999999 is prime; 9+9+9+9+9+9+9+9+9+8+9+8+7 = 113 is prime; the reversal 311 is prime. [Post]

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