Number Gossip

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Unique Properties of 504

  • 504 is the smallest number n, such that σ(x) = n has exactly ten solutions, where σ(x) means the sum of the divisors
  • 504 is the smallest sum of numbers in an amicable pair
  • 504 is the smallest number with two pairs of divisors that multiply to the number itself and are reverses of each other (504 = 42*12 = 24*21)
  • 504 is the smallest number such that the digits of σ(n) are a permutation of the digits of σ(n)-n

Common Properties of 504