49 (number)

← 48 49 50 →
Cardinalforty-nine
Ordinal49th
(forty-ninth)
Factorization72
Divisors1, 7, 49
Greek numeralΜΘ´
Roman numeralXLIX
Binary1100012
Ternary12113
Quaternary3014
Quinary1445
Senary1216
Octal618
Duodecimal4112
Hexadecimal3116
Vigesimal2920
Base 361D36

49 (forty-nine) is the natural number following 48 and preceding 50.

In mathematics

Forty-nine is the square of seven

The sum of the digits of the square of 49 (2401) is the square root of 49.

49 is the first square where the digits are squares. In this case 4 and 9 are squares.

It appears in the Padovan sequence, preceded by the terms 21, 28, 37 (it is the sum of the first two of these).[1]

Along with the number that immediately derives from it, 77, the only number under 3 digits not having its home prime known (as of late 2010).

Reciprocal

The fraction 1/49 is a repeating decimal with a period of 42:

1/49 = 0.0204081632 6530612244 8979591836 7346938775 51 (42 digits repeat)

There are 42 (note that this number is the period) positive integers that are less than 49 and coprime to 49. Multiplying 020408163265306122448979591836734693877551 by each of these integers results in a cyclic permutation of the original number:

  • 020408163265306122448979591836734693877551 × 2 = 040816326530612244897959183673469387755102
  • 020408163265306122448979591836734693877551 × 3 = 061224489795918367346938775510204081632653
  • 020408163265306122448979591836734693877551 × 4 = 081632653061224489795918367346938775510204
  • ...

The repeating number can be obtained from 02 and repetition of doubles placed at two places to the right:

02
  04
    08
      16
        32
          64
           128
             256
               512
                1024
                  2048
+                   ...
----------------------
020408163265306122448979591836734693877551...0204081632...
Other Languages
العربية: 49 (عدد)
azərbaycanca: 49 (ədəd)
تۆرکجه: ۴۹ (سایی)
Bân-lâm-gú: 49
български: 49 (число)
བོད་ཡིག: ༤༩ (གྲངས་ཀ།)
català: Quaranta-nou
Чӑвашла: 49 (хисеп)
čeština: 49 (číslo)
dansk: 49 (tal)
Ελληνικά: 49 (αριθμός)
emiliàn e rumagnòl: 49 (nùmer)
Esperanto: 49 (nombro)
فارسی: ۴۹ (عدد)
français: 49 (nombre)
Gaeilge: 49 (uimhir)
贛語: 49
한국어: 49
հայերեն: 49 (թիվ)
हिन्दी: ४९
Bahasa Indonesia: 49 (angka)
interlingua: 49 (numero)
italiano: 49 (numero)
עברית: 49 (מספר)
ქართული: 49 (რიცხვი)
Kiswahili: Arubaini na tisa
Kreyòl ayisyen: 49 (nonm)
latviešu: 49 (skaitlis)
lietuvių: 49 (skaičius)
magyar: 49 (szám)
македонски: 49 (број)
Bahasa Melayu: 49 (nombor)
Mìng-dĕ̤ng-ngṳ̄: 49
Nederlands: 49 (getal)
日本語: 49
Napulitano: Quarantanòve
norsk: 49 (tall)
norsk nynorsk: Talet 49
oʻzbekcha/ўзбекча: 49 (son)
پنجابی: 49
پښتو: ۴۹ (عدد)
polski: 49 (liczba)
português: Quarenta e nove
русский: 49 (число)
Sesotho sa Leboa: 49 (nomoro)
Simple English: 49 (number)
slovenščina: 49 (število)
Soomaaliga: 49 (tiro)
کوردی: ٤٩ (ژمارە)
Sranantongo: Numro 49
српски / srpski: 49 (број)
suomi: 49 (luku)
svenska: 49 (tal)
татарча/tatarça: 49 (сан)
ไทย: 49
Türkçe: 49 (sayı)
українська: 49 (число)
اردو: 49 (عدد)
Vahcuengh: 49
Tiếng Việt: 49 (số)
Winaray: 49 (ihap)
ייִדיש: 49 (נומער)
粵語: 49
中文: 49