This number is a prime.

+ The prime number 21661 can be obtained with the quadratic form 2x^2-4x+31, where x = 105. [Sandri]

+ There are 18 cases of the nth distinct digit brilliant number being divisible by n. The largest is the 21661st (430815629) being divisible by 21661. [Gaydos]

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