The book is now available! 609
(another Prime Pages' Curiosity)
Prime Curios!
Curios: Curios Search:
 

Participate:
Share
+ 100^609 - 609 is prime. Note that 609 is the third number with this property. [Firoozbakht]

+ n = 609 = 5^2^2 - 2^2^2 is the (5^2)th natural number with the property p = n^2 + 2 is prime; additionally (p - 2^2, p) is a pair of prime cousins. Note that n^2 - (2*5) and n^2 + (2*5) are primes too! [Herault]

+ pi(609) is strobogrammatic. The only known case greater than 1. [Resta]




Prime Curios! © 2000-2017 (all rights reserved)