# JAVASCRIPT NUMBER

The Number is a primitive data type. *Number* represents all numerical values like integer, float, exponential etc.

Generally browsers automatically convert Number literals to instances of Number class.

The normal way of defining a number is * Number literal*. Lets see an example.

Example: Number using Literal Syntax

## Creating Javascript Number Using Constructor

To create number using number constructor use `Number()`

as function/constructor and pass the number as argument. Example `Number(20)`

, `Number(35.5)`

etc.

Example: Number using Constructor

## Ways to write a number in Javascript

Generally there are three ways of writing a Number in javascript.

- Decimal method
- Exponential method
- Other Number SystemOther Number System

### 1. Decimal Method

We use the Decimal system for our general use, like 9,10,12.3,5.5 etc. Defining numbers in this form is the decimal method.

### 2. Exponential Method

While writing numbers line 1 billion or 1 trillion in numbers we would have to write like 100000000 and 10000000000 respectively.

Javascript also provides a method to write such numbers in an easier manner. We can shorten the number by appending `"e"`

to the number and then specifying the number of 0's after it. Example, 1000 can be written as 1e3, 0.002 as 2e-3, 50000 as 5e4 etc.

Example: Exponential method

### 3. Other Number System

There exist other number systems apart from decimal like **binary**, **octal** and **hexadecimal**.

**hexadecimal numbers** are widely used in the hex color system.

The hexadecimal number is defined by suffix

in the number. example 0xff, 0x25 etc.**0x**

Example: Hexadecimal number

Binary number number includes only 2 numbers 0 and 1. It is defined by

in the starting of the number. example 0b1010, 0x11 etc.**0b**

Example: Binary number

Octal number includes 8 numbers 0,1,2,3,4,5,6 and 7. It is defined by

in the starting of the number. example 0o45, 0x22 etc.**0o**

Example: Octal number

## Javascript Number Property

As Number is a global object it has some properties.

All the properties of Number are static like properties of math.

Method | Description |
---|---|

Number.EPSILON | The smallest interval between two numbers |

Number.MAX_VALUE | The largest positive representable number |

Number.MAX_SAFE_INTEGER | Maximum safe integer in javascript is 2^{53} - 1 |

Number.MIN_VALUE | The smallest positive representable number. Smallest number just greater than 0 |

Number.MIN_SAFE_INTEGER | Minimum safe integer in javascript is -(2^{53} - 1) |

Number.NaN | Not a Number |

Number.NEGATIVE_INFINITY | Represent negative Infinity |

Number.POSITIVE_INFINITY | Represent positive Infinity |

Example: Number Properties

## Javascript Number methods

Method | Description |
---|---|

toString() | Return number as a string |

toExponential() | Return number as string with number written in exponential form |

toFixed() | Return number as a string with number of decimals specified |

toPrecision() | Return number as a string, with specified length |

valueOf() | Return calculated value in number, we can pass expression a argument |

Example: Number Method