123456791
This number is a prime.
 
The sum of all repunit numbers R1 through R9 plus 2.  [Loungrides]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Reginald McLean
This number is a prime.
 
The sum of all repunit numbers R1 through R9 plus 2.  [Loungrides]