122 (number)

Last updated
121 122 123
Cardinal one hundred twenty-two
Ordinal 122nd
(one hundred twenty-second)
Factorization 2 × 61
Divisors 1, 2, 61, 122
Greek numeral ΡΚΒ´
Roman numeral CXXII
Binary 11110102
Ternary 111123
Senary 3226
Octal 1728
Duodecimal A212
Hexadecimal 7A16

122 (one hundred [and] twenty-two) is the natural number following 121 and preceding 123.

Contents

In mathematics

122 is a nontotient since there is no integer with exactly 122 coprimes below it. Nor is there an integer with exactly 122 integers with common factors below it, making 122 a noncototient.

122 is a semiprime.

122 is the sum of squares of the divisors of 11.

φ(122) = φ(σ(122)). [1]

In other fields

See also

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References

  1. Sloane, N. J. A. (ed.). "SequenceA006872". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.