84 (number)

84 (eighty-four) is the natural number following 83 and preceding 85.

List of numbers — Integers << 80 81 82 83 84 85 86 87 88 89 >>
Cardinal	eighty-four
Ordinal	84th (eighty-fourth)
Factorization	<math> 2^2 \cdot 3 \cdot 7<math>
Divisors	2, 3, 4, 6, 7, 12, 14, 21, 28, 42
Roman numeral	LXXXIV
Binary	01010100
Hexadecimal	54

In mathematics

Eighty-four is the sum of the first seven triangular numbers (making it a tetrahedral number), as well as the sum of a twin prime (41 + 43).

In other fields

Eighty-four is also:

• the atomic number of polonium (Po)
• the model number of AGM-84 Harpoon
• WGS 84
• the house number of 84 Avenue Foch
• the number of the French department Vaucluse
• the designation of Interstate 84, a freeway that runs from Oregon to Utah and from Pennsylvania to Massachusetts.
• the code for international direct dial phone calls to Vietnam
• a town in Pennsylvania: Eighty Four
• The year AD 83, 83 BC, or 1983.
• The number of earth-years it takes the planet Uranus to make one complete revolution around the Sun.