World Library  
Flag as Inappropriate
Email this Article

38 (number)

Article Id: WHEBN0000363207
Reproduction Date:

Title: 38 (number)  
Author: World Heritage Encyclopedia
Language: English
Subject: 39 (number), 37 (number), 30 (number), 33 (number), 34 (number)
Collection: Integers
Publisher: World Heritage Encyclopedia

38 (number)

37 38 39
Cardinal thirty-eight
Ordinal 38th
Factorization 2 × 19
Divisors 1, 2, 19, 38
Roman numeral XXXVIII
Binary 1001102
Ternary 11023
Quaternary 2124
Quinary 1235
Senary 1026
Octal 468
Duodecimal 3212
Hexadecimal 2616
Vigesimal 1I20
Base 36 1236

38 (thirty-eight) is the natural number following 37 and preceding 39.


  • In mathematics 1
  • In science 2
    • Astronomy 2.1
  • In other fields 3
  • References 4

In mathematics

38 is the 11th distinct semiprime and the 7th in the {2.q} family. It is the initial member of the third distinct semiprime pair (38, 39).

38 has an aliquot sum of 22 which is itself a distinct semiprime In fact 38 is the first number to be at the head of a chain of four distinct semiprimes in its 8-member aliquot sequence (38, 22, 14, 10, 8, 7, 1, 0). 38 is the 8th member of the 7-aliquot tree.

38! - 1 yields 523022617466601111760007224100074291199999999, which is the 16th factorial prime.

There is no answer to the equation φ(x) = 38, making 38 a nontotient.[1]

38 is the sum of the squares of the first three primes.

37 and 38 are the first pair of consecutive positive integers not divisible by any of their digits.

38 is the largest even number which cannot be written as the sum of two odd composite numbers.

There are only two normal magic hexagons, order 1 (which is trivial) and order 3. The sum of each row of an order 3 magic hexagon is 38.[2]

In science


In other fields

Most people will see the number 38, but people with red-green color blindness might see 88 instead.

Thirty-eight is also:


  1. ^ (sequence A005277 in OEIS)
  2. ^ Higgins, Peter (2008). Number Story: From Counting to Cryptography. New York: Copernicus. p. 53.  
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.