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Working with Numbers

So we looked at strings and the properties and methods that are available to us. Now let's look at numbers. We'll also look at the Math object.

Like with strings, when we add a method to a number, a new number object is created and we can use that object to call the method. Let's create the object ourselves to see the available methods in the prototype

const num = new Number(5);
console.log(num)

number-object

toString()​

Returns a string representation of the number

num.toString(); // "5"

Number types and objects do not have a length property. If you want to find the length, one thing that you could do is convert it to a string and then use length

num.toString().length; // 1

toFixed()​

Returns a string representation of the number with a specified number of decimals

Let's assume num is equal to 5 right now

num.toFixed(2); // 5.00
num.toFixed(1); // 5.0

toPrecision()​

returns a number with the specified length

const num2 = 94.4058;
num.toPrecision(3); // 94.4

toExponential()​

Returns a string representation of the number in exponential notation

num.toExponential(2); // "5.00e+0"

toLocalString()​

Returns a string representation of the number in the current locale

let num = 5000000;
num.toLocalString(); // "5,000,000"

It defaults to the browser's locale, which for me is "en-US", but let's say we want to use India's locale

num.toLocalString('en-IN'); // "50,00,000"

Number Object Properties & Values​

The Number object has a few properties and methods that are available.

Max Value​

Largest possible value of a number

Number.MAX_VALUE; // 1.7976931348623157e+308

Min Value​

Smallest possible value of a number

Number.MIN_VALUE; // 5e-324

There are methods as well. For instance, we already looked at isNaN(), which will tell us if the value is actually NaN

Number.isNaN(NaN); // true