42857...57143 (68-digits)

This number is a prime.

  42857142 8571428571 4285714285 7142857142 8571428571 4285714285 7142857143

Just showing those entries submitted by 'Glenn': (Click here to show all)

The prime number ((3 x 10⁶⁸) + 1)/7 contains the first 68 digits of the decimal expansion of 3/7 rounded up. [Glenn]