Number Gossip

(Enter a number and I'll tell you everything you wanted to know about it but were afraid to ask.)

Unique Properties of 22

  • 22 is the smallest Hoax Number
  • 22 is the smallest multidigit number such that the sum of its digits equals the product of its digits
  • 22 is the only fixed point of the Look and Say operation
  • 22 is the smallest number that can be partitioned into sets integers such that the sum of their reciprocals is 1 in more than one way
  • 22 is famous as the numerator of of 22/7, commonly used rational approximation for pi with small denominator
  • When cutting a circle with just six line segments, the maximum number of pieces that can be so created is 22. In addition to that, cutting a circle with five circles, the maximum number of pieces is also 22
  • 22 is a catch, as in Catch-22
  • 22 is the only palindrome with an even number of digits that can be expressed as a sum of two palindromic primes
  • 22 is the smallest number that is the sum of terms of an arithmetic progression containing four positive different integers in two ways
  • 22 is the smallest integer n, except for the trivial 1, such that n! has n digits
  • There are 22 pentahexes

Rare Properties of 22

Pentagonal

Common Properties of 22

Composite
Deficient
Even
Lazy caterer
Odious
Palindrome
Smith (Joke)
Square-free