Number Gossip

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Unique Properties of 263

  • 263 is the smallest prime such that it stays prime after adding or subtracting its largest digit
  • 263 is the smallest prime for which the sum of reciprocals of nonzero digits equals 1
  • 263 is the smallest prime base 10 that is never prime in any smaller base expansions interpreted as decimal numbers

Common Properties of 263

Deficient
Evil
Happy
Odd
Prime
Square-free