222 (number)

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221 222 223
Cardinal two hundred twenty-two
Ordinal 222nd
(two hundred and twenty-second)
Factorization 2 × 3 × 37
Roman numeral CCXXII
Binary 110111102
Ternary 220203
Quaternary 31324
Quinary 13425
Senary 10106
Octal 3368
Duodecimal 16612
Hexadecimal DE16
Vigesimal B220
Base 36 6636

222 (two hundred [and] twenty-two) is the natural number following 221 and preceding 223.

It is a decimal repdigit[1] and a strobogrammatic number (meaning that it looks the same turned upside down on a calculator display).[2] It is one of the numbers whose digit sum in decimal is the same as it is in binary.[3]

222 is a noncototient, meaning that it cannot be written in the form n − φ(n) where φ is Euler's totient function counting the number of values that are smaller than n and relatively prime to it.[4]

There are exactly 222 distinct ways of assigning a meet and join operation to a set of ten unlabeled elements in order to give them the structure of a lattice,[5] and exactly 222 different six-edge polysticks.[6]

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