138 (number)

Last updated
← 137 138 139 →
Cardinal one hundred thirty-eight
Ordinal 138th
(one hundred thirty-eighth)
Factorization 2 × 3 × 23
Divisors 1, 2, 3, 6, 23, 46, 69, 138
Greek numeral ΡΛΗ´
Roman numeral CXXXVIII, cxxxviii
Binary 100010102
Ternary 120103
Senary 3506
Octal 2128
Duodecimal B612
Hexadecimal 8A16

138 (one hundred [and] thirty-eight) is the natural number following 137 and preceding 139.

Mathematics

138 is a sphenic number, [1] an Ulam number, [2] an abundant number, [3] and a square-free congruent number. [4]

Four concentric magic circles, with a magic constant of 138. Yang Hui magic circle.svg
Four concentric magic circles, with a magic constant of 138.

References

  1. ↑ Sloane, N. J. A. (ed.). "SequenceA007304(Sphenic numbers: products of 3 distinct primes.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-07-24.
  2. ↑ Sloane, N. J. A. (ed.). "SequenceA002858(Ulam numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-07-24.
  3. ↑ Sloane, N. J. A. (ed.). "SequenceA005101(Abundant numbers (sum of divisors of m exceeds 2m).)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-07-24.
  4. ↑ Sloane, N. J. A. (ed.). "SequenceA006991(Primitive congruent numbers.)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation. Retrieved 2023-07-24.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.