249 (number)

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249 (two hundred [and] forty-nine) is the natural number following 248 and preceding 250.

← 248 249 250 →
Cardinaltwo hundred forty-nine
Ordinal249th
(two hundred forty-ninth)
Factorization3 × 83
Greek numeralΣΜΘ´
Roman numeralCCXLIX
Binary111110012
Ternary1000203
Quaternary33214
Quinary14445
Senary10536
Octal3718
Duodecimal18912
HexadecimalF916
VigesimalC920
Base 366X36

In mathematics[edit]

249 is:

  • a Blum integer.[1]
  • a semiprime.
  • palindromic in bases 82 (3382) and 248 (11248).
  • a Harshad number in bases 3, 83, 84, 124, 167 and 247.
  • the aliquot sum of any of these numbers: 375, 531, 1687, 4351, 7807, 12127, 14647 and 15151.
  • part of the 3-aliquot tree. The aliquot sequence starting at 288 is: 288, 531, 249, 87, 33, 15, 9, 4, 3, 1, 0.

References[edit]

  1. ^ "Sloane's A016105 : Blum integers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-28.