75 (number)

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75 (seventy-five) is the natural number following 74 and preceding 76.

<< 70 71 72 73 74 75 76 77 78 79 >> List of numbers -- Integers 0 10 20 30 40 50 60 70 80 90 >>
Cardinal	75 seventy-five
Ordinal	75th seventy-fifth
Factorization	$3 \cdot 5^2$
Divisors	1, 3, 5, 15, 25, 75
Roman numeral	LXXV
Binary	1001011
Hexadecimal	4B

[edit] In mathematics

As the sum of the first five pentagonal numbers, seventy-five is a pentagonal pyramidal number. It is also an enneagonal number.

It is also a Keith number, because it recurs in a Fibonacci-like sequence started from its base 10 digits: 7, 5, 12, 17, 29, 46, 75... But there is no integer that added up to its own digits adds up to 75, hence 75 is a self number.

There are 75 uniform polyhedra.

[edit] In astronomy

Messier object M75, a magnitude 9.5 globular cluster in the constellation Sagittarius

The New General Catalogue object NGC 75, a spiral galaxy in the constellation Pisces

[edit] In other fields

Seventy-five is also:

The atomic number of rhenium
The age limit for Canadian senators
The designation of Interstate 75, a freeway that runs from Florida to Michigan.
The registry of the U.S. Navy's nuclear aircraft carrier USS Harry S. Truman (CVN-75), named after U.S. President Harry S. Truman.
The record for most game show wins, held by Ian Lygo. Also, the record for most game show appearances, currently a tie between Lygo and Ken Jennings.
The year AD 75, 75 BC, or 1975.
A common speed limit, in terms of miles per hour, in the western United States.