Number Gossip

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Unique Properties of 61

  • The 61st Fibonacci number (2504730781961) is the smallest Fibonacci number which contains all the digits from 0 to 9
  • 61 is the smallest multi-digit prime p such that the sum of digits of pp is a square
  • 61 is the smallest prime whose reversal is a square
  • 61 is the smallest number n such that the reversal of concatenation of the first n natural numbers is prime
  • 61 is the smallest prime p such that p# is pandigital
  • The earliest series of ten consecutive distinct digits of pi begin at the 61st digit

Common Properties of 61