8

This number is a composite.

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

+ 8 is the smallest cube that is the sum of two consecutive Sophie Germain primes (3 + 5). Can you find the next cube with this property? [Gaydos]

+ 8 is the last digit to appear in both a prime number and its prime index, first appearing in 787 and 138. The other 9 digits all first appear in smaller prime-prime index pairs. [Gaydos]

(There are 5 curios for this number that have not yet been approved by an editor.)

Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell