69 (number)

From Wikipedia, the free encyclopedia

← 60 61 62 63 64 65 66 67 68 69 → List of numbers — Integers 0 10 20 30 40 50 60 70 80 90 →
Cardinal	69 sixty-nine
Ordinal	69th sixty-ninth
Numeral system	sexagesimal
Factorization
Divisors	1, 3, 23, 69
Roman numeral	LXIX
Binary	1000101
Octal	105
Duodecimal	59
Hexadecimal	45

69 (sixty-nine) is the natural number following 68 and preceding 70.

[edit] In mathematics

Adding up the divisors of 1 through 9 gives 69.

Because 69 has an odd number of 1s in its binary representation, it is sometimes called an "odious number"

Something to note is that 69³² = 6969007...

Another thing to note is that 69² (4 761) and 69³ (328 509) uses every digit from 0-9.

69 is equal to 105 octal, while 105 is equal to 69 hexadecimal. This same property can be applied to all numbers from 64 to 69.

69 is a semiprime.

On many handheld scientific and graphing calculators, the highest factorial that can be computed within memory limitations is 69! or 1.711224524*10⁹⁸.

[edit] In science

• The atomic number of thulium, a lanthanide

[edit] Astronomy

The Messier object M69 is a magnitude 9.0 globular cluster in the constellation Sagittarius.