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Unique Properties of 131

  • The 131st Fibonacci number (1066340417491710595814572169) is the smallest Fibonacci prime which contains all the digits from 0 to 9
  • 131 is the smallest number n such that n + 1 and n − 1 each has exactly 3 distinct prime factors
  • 131 is the smallest Honaker prime: the sum of its digits equals the sum of the digits of its index (32) in the prime sequence
  • 131 is the smallest prime that is a concatenation of a prime and its first digit
  • 131 is the smallest palindromic prime made of only two digits such that swapping those digits creates another prime
  • 131 is the smallest prime which stays prime when the end digits (on both sides) are repeated once (11311 is also prime)
  • 131 is the smallest mountain prime
  • 131 is the smallest palindromic prime with three primes embedded in it (13, 3 and 31)

Rare Properties of 131

Palindromic prime

Common Properties of 131