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140

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140 is an integer, and a harmonic divisor number (see A001599), the second one not to be an even perfect number.

Membership in core sequences

Even numbers ..., 134, 136, 138, 140, 142, 144, 146, ... A005843
Composite numbers ..., 135, 136, 138, 140, 141, 142, 143, ... A002808
Abundant numbers ..., 126, 132, 138, 140, 144, 150, 156, ... A005101
Square pyramidal numbers ..., 30, 55, 91, 140, 204, 285, 385, 506, ... A000330

Sequences pertaining to 140

Divisors of 140 1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140 A018301
Multiples of 140 0, 140, 280, 420, 560, 700, 840, 980, 1120, 1260, 1400, 1540, ...
sequence beginning at 63 63, 188, 94, 47, 140, 70, 35, 104, 52, 26, 13, 38, 19, 56, 28, ... A008895

Note that 140 has twelve divisors which add up to 336. The harmonic mean is therefore , and since that's an integer, 140 is a harmonic divisor number (A001599).

Partitions of 140

There are 15065878135 partitions of 140.

The Goldbach representations of 140 are: 137 + 3 = 127 + 13 = 109 + 31 = 103 + 37 = 97 + 43 = 79 + 61 = 73 + 67 = 140.

Roots and powers of 140

In the table below, irrational numbers are given truncated to eight decimal places.

PLACEHOLDER

Values for number theoretic functions with 140 as an argument

PLACEHOLDER

Factorization of some small integers in a quadratic integer ring adjoining −140, 140

PLACEHOLDER

Factorization of 140 in some quadratic integer rings

PLACEHOLDER

TABLE GOES HERE

Representation of 140 in various bases

Base 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Representation 10001100 12012 2030 1030 352 260 214 165 140 118 B8 AA A0 95 8C 84 7E 77 70

140 is a Harshad number in bases 4, 5, 6, 8, 10, 11, 13, 14, 15, 16, 19, 20, etc.

See also

Some integers
0 1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19
20 21 22 23 24 25 26 27 28 29
30 31 32 33 34 35 36 37 38 39
40 41 42 43 44 45 46 47 48 49
1729