Number Gossip

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Unique Properties of 1680

  • 1680 is the smallest number with 40 divisors
  • 1680 is the smallest area of a triangle with sides, area, and two medians being integers
  • 1680 is the smallest number n such that 2n − 1 is less than σ(n) &minus σ(n-2). Equivalently, 1680 is the smallest n such that the sum of non-divisors of n is less than the sum of non-divisors of n-2
  • 1680 is the smallest number n such that 2n - φ(x) = σ(x)/2

Common Properties of 1680

Abundant
Composite
Even
Evil
Practical
Untouchable