10000...00081 (144-digits)

This number is a prime.

                                                                        1000
0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000
0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000081

10^143 + 3^4 is the smallest prime with a gross of digits. [Patterson]