23

This number is a prime.

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

Kristen Eller ©2002
+ The smallest safe prime that equals to the sum of the previous n safe primes (n=3). [Loungrides]

+ The smallest multidigit prime that is simultaneously a left-truncatable prime and right-truncatable prime. [Loungrides]

+ The smallest prime that yields another prime if the next prime is sandwiched between its digits, i.e., 2293. [Loungrides]

+ (23, 29) is the only pair of consecutive double-digit primes p, q, such that the sum of digits of p^5 is equal to q and the sum of digits of q^5 is equal to p, (23^5=6436343 (whose sum of digits is 29) and 29^5=20511149 (whose sum of digits is 23). [Loungrides]

+ (17, 19, 23) is the only known triplet of multidigit consecutive primes p < q < r such that r|pq-1. [Loungrides]

+ (23, 29) is the only pair (p, q), of two consecutive double-digit primes (p < q), such that p^2+q^3-/+1, is a twin prime pair, i.e., (24917, 24919). [Loungrides]

(There are 6 curios for this number that have not yet been approved by an editor.)

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