124 (number)

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← 123 124 125 →
Cardinalone hundred twenty-four
Ordinal124th
(one hundred twenty-fourth)
Factorization22 × 31
Divisors1, 2, 4, 31, 62, 124
Greek numeralΡΚΔ´
Roman numeralCXXIV
Binary11111002
Ternary111213
Senary3246
Octal1748
DuodecimalA412
Hexadecimal7C16

124 (one hundred [and] twenty-four) is the natural number following 123 and preceding 125.

In mathematics[edit]

124 magnetic balls arranged into the shape of a stella octangula

124 is an untouchable number, meaning that it is not the sum of proper divisors of any positive number.[1]

It is a stella octangula number, the number of spheres packed in the shape of a stellated octahedron.[2] It is also an icosahedral number.[3]

There are 124 different polygons of length 12 formed by edges of the integer lattice, counting two polygons as the same only when one is a translated copy of the other.[4]

124 is a perfectly partitioned number, meaning that it divides the number of partitions of 124. It is the first number to do so after 1, 2, and 3.[5]

See also[edit]

References[edit]

  1. ^ Sloane, N. J. A. (ed.). "Sequence A005114 (Untouchable numbers, also called nonaliquot numbers: impossible values for the sum of aliquot parts function)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  2. ^ Sloane, N. J. A. (ed.). "Sequence A007588 (Stella octangula numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  3. ^ Sloane, N. J. A. (ed.). "Sequence A006564 (Icosahedral numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  4. ^ Sloane, N. J. A. (ed.). "Sequence A002931 (Number of self-avoiding polygons of length 2n on square lattice (not allowing rotations))". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  5. ^ Sloane, N. J. A. (ed.). "Sequence A051177 (Perfectly partitioned numbers: numbers k that divide the number of partitions p(k))". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.