107101153249117163363

This number is a prime.

                                                     1 0710115324 9117163363

The smallest 21-digit emirp that remains an emirp after rightmost digits are omitted three at a time, i.e., 107101153249117163363, 107101153249117163, 107101153249117, 107101153249, 107101153, 107101, 107 are all emirps. [Loungrides]