49 (number)

49

← 40 41 42 43 44 45 46 47 48 49 →

List of numbers — Integers

← 0 10 20 30 40 50 60 70 80 90 →

forty-nine

49th
(forty-ninth)

7²

1, 7, 49

XLIX

110001₂

1211₃

301₄

144₅

121₆

61₈

41₁₂

31₁₆

29₂₀

1D₃₆

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

The aliquot sum of forty-nine is 8, and this number has an aliquot sequence of (8, 7, 1, 0).

49 is the 8th composite number in the 7-aliquot tree.

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).

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).

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

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:

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

Forty-nine is:

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