1111111111111

This number is a composite.

                                                              111 1111111111

+



            1
         1 1 1 1
          1 1 1
         1 1 1 1
            1

A star-congruent prime of order 2 in bases 2 and 5. [Dobb]

+ The smallest repunit 3-almost prime, i.e., containing three prime factors (1111111111111 = 53*79*265371653). [Gupta]

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