Number
In mathematics, a number was an object represented by a numeral used to depict a qualitative value that could be used for a variety of purposes, ranging from counting to performing more complex mathematical functions. They were generally assigned for purposes of identification or prioritization. 

Numbers could be said to be odd or even (, ), and positive or negative. () There were also at least six prime numbers. ()

Harry Mudd's androids were each numbered from 1 to 500. ()

Numbers with significant meanings 
One (1)

Two (2)

Three (3)
 

Twelve (12)

Twenty (20)

Twenty-one (21)
 According to Data, the card game known as "blackjack", also known as "21", "a number which defines the object of the game." ()

One-hundred forty-four (144)

See also 
 Employee number
 Fraction
 Lot number
 Omega constant
 Order of magnitude 
 
 Thousand
 Million
 Billion
 Trillion
 Quadrillion
 Phone number
 
 Registry number
 Roman numeral
 Serial number

External link 
 
Mathematics