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Number in Javascript
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In JavaScript, numbers can be stored as primitive values (like 10 or 102.7) or as objects using the Number object.
The Number object helps represent numeric values, whether integers, floating-point numbers, or values in exponent notation.



How to Create Number Objects

You can crate number objects in two ways


Using Number constructor

var n = new Number(10);


Directly assign numbers to variables

var x = 102;          // integer
var y = 102.7;        // floating-point number
var z = 13e4;         // exponent notation, equals 130000



Example:

<!DOCTYPE html>
<html>

<body>
    <script>
        var x = 102;                // integer value  
        var y = 102.7;              // floating point value  
        var z = 13e4;               // exponent value (130000)  
        var n = new Number(10);     // number object  
        document.write(x + " " + y + " " + z + " " + n);
    </script>
</body>

</html>

Output

Uploaded Image




Number Constants

JavaScript also provides predefined number constants like

  • Number.MAX_VALUE – Largest representable number
  • Number.MIN_VALUE – Smallest positive number
  • Number.POSITIVE_INFINITY – Infinity
  • Number.NEGATIVE_INFINITY – -Infinity
  • Number.NaN – Not a Number



Number Methods

Numbers in JavaScript can use methods (thanks to auto-boxing, where primitive numbers are temporarily wrapped as Number objects).



Example:

let num = 3.14159;

let str = num.toString();    // Convert number to string
console.log(str);            // Output: "3.14159"

let fixed = num.toFixed(2);  // Round to two decimal places
console.log(fixed);          // Output: "3.14"



Key Point

  • JavaScript automatically handles numbers as primitive values or objects when needed.
  • Number objects are rarely used, but methods like toString(), toFixed(), and toPrecision() are very useful.
  • Supports integers, floating points, and exponent notation.