Number Gossip

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Unique Properties of 2161

  • 2161 is the smallest prime such that deleting a digit results in a prime with the same multiplicative order or period
  • 2161 is the smallest prime which is a digital reversal of products of emirpimes pairs: 1612 = 26 * 62 (emirpimes pairs are pairs of distint semiprimes that are reverses of each other)

Common Properties of 2161

Apocalyptic power
Deficient
Odd
Odious
Prime
Square-free