Number | NN 3 IE J2 ECMA 1
A Number object represents any numerical value, whether it is an integer or floating-point number. By and large, you don't have to worry about the Number object because a numerical value automatically becomes a Number object instance whenever you use such a value or assign it to a variable. On the other hand, you might want access to the static properties that only a math major would love.
Creating a Number Object
    var myValue = number
    var myValue = new Number(number)

MAX_VALUE | NN 3 IE J2 ECMA 1
| Read-only
Equal to the highest possible number that JavaScript can handle.
Example
    var tiptop = Number.MAX_VALUE
Value 1.7976931348623157e+308

MIN_VALUE | NN 3 IE J2 ECMA 1
| Read-only
Equal to the smallest possible number that JavaScript can handle.
Example
    var itsybitsy = Number.MIN_VALUE
Value 5e-324

NaN | NN 3 IE J2 ECMA 1
| Read-only
Equal to a value that is not-a-number. JavaScript returns this value when a numerical operation yields a non-numerical result because of a flaw in one of the operands. If you want to test whether a value is not a number, use the isNaN() global function rather than comparing to this property value.
Value NaN

NEGATIVE_INFINITY, POSITIVE_INFINITY | NN 3 IE J2 ECMA 1
| Read-only
Values that are outside of the bounds of Number.MIN_VALUE and Number.MAX_VALUE, respectively.
Example
    Number.NEGATIVE_INFINITY
Value -Infinity; Infinity

prototype | NN 3 IE J2 ECMA 1
| Read/Write
A property of the static Number object. Use the prototype property to assign new properties and methods to future instances of a Number value created in the current document. See the Array.prototype property description for examples. There is little need to create new prototype properties or methods for the Number object.
Example
    Number.prototype.author = "DG"
Value Any data, including function references.

toString() | NN 4 IE J3 ECMA 1
Returns the object's value as a string data type. You don't need this method in practice because the browsers automatically convert Number values to strings when they are needed for display in alert dialogs or in-document rendering.
Returned Value String.
Parameters None.

valueOf() | NN 4 IE J3 ECMA 1
Returns the object's value.
Returned Value A numeric value.
Parameters None.