777777
This number is a composite.
Single Curio View: (Seek other curios for this number)
The only six-digit repdigit such that the sum of itself and
all truncations of itself minus one, i.e.,
777777+77777+7777+777+77+7 - 1 = 864191 is prime. [Bajpai]
Submitted: 2017-04-19 14:02:14; Last Modified: 2020-06-15 19:52:11.
Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell