Search a number
hyperperfect n.  and  repunit

Search a number

(max 15 digits)

First numbers that belong to both sets:

21, 1333, 16513, 37021141, 65618101, 688773781, 796622401, 3662246773, 6879790081, 43237588033, 337148035381, 849347481601, 1008025036021, 1421971583761, 1453482210421, 1951956868501.