# TypeScript Numbers: Exploring TypeScript Data Type “Numbers”

## What is a TypeScript number?

A number in TypeScript is a basic data type that represents numeric values.

Here’s an easier way to understand it:

How to Declare:

You can create a number variable like the following:

let age: number = 18;

Arithmetic Operations:

Arithmetic operations can be performed with numbers.

For instance:

let sum: number = x + y;

Increment and Decrement:

The increment (++) and decrement (–) operators can be used to change number variables.

## TypeScript Numbers Common properties

The following are the common properties of the number object:

1. MAX_VALUE

The MAX_VALUE represents the largest possible numeric value.

console.log(Number.MAX_VALUE);

Output:

1.7976931348623157e+308

1. MIN_VALUE

The MIN_VALUE is the smallest possible positive value.

console.log(Number.MIN_VALUE)

Output:

5e-324

1. NaN

It refers to a value that is not a number.

console.log(Number.NaN); // Outputs: NaN
console.log(isNaN('itsourcecode')); // Outputs: true
console.log(isNaN(143)); // Outputs: false

1. NEGATIVE_INFINITY

The NEGATIVE_INFINITY represents a value that is less than MIN_VALUE.

console.log(Number.NEGATIVE_INFINITY);
console.log(-1 / 0);

Output:

-Infinity
-Infinity

1. POSITIVE_INFINITY

The POSITIVE_INFINITY is a value that is greater than MAX_VALUE.

console.log(Number.POSITIVE_INFINITY);
console.log(1 / 0);

Output:

Infinity
Infinity

1. Prototype

The Number object has a static property.
You can use the prototype property to add new properties and methods to the Number object in the current document.

### Constructor

This refers to the function that was used to create the instance of this object. Typically, this is the Number object.

## Number Methods

TypeScript offers several methods for working with numbers:

### 1. toFixed()

The toFixed() method formats a number with a specific number of decimal places and returns it as a string.

Syntax:

numObj.toFixed([digits])

For example:

let num = 12.3456789;
console.log(num.toFixed(3));

Output:

12.346

### 2. toExponential()

The toExponential() method returns a string representation of a number in exponential notation.

Syntax:

numObj.toExponential([fractionDigits])

For example:

let num = 1020304050;
console.log(num.toExponential());

Output:

1.02030405e+9

### 3. toLocaleString()

The toLocaleString() method formats the number into a local-specific representation of a number.

Syntax:

numObj.toLocaleString([locales [, options]])

For example:

let num = 102030405060.708090;
console.log(num.toLocaleString());

Output:

102,030,405,060.708

### 4. toPrecision()

The toPrecision() method returns a string representation of a number using the specified precision.

Syntax:

numObj.toPrecision([precision])

For example:

let num = 1.23456789;
console.log(num.toPrecision(4));

Output:

1.235

### 5. toString()

The toString() method converts a number to its string representation.

Syntax:

For example:

let num = 102030;
console.log(num.toString());

Output:

102030

### 6. valueOf()

The valueOf() method returns the primitive value of the number.

Syntax:

numObj.valueOf()

For example:

let num = new Number(10203040);
console.log(num.valueOf());

Output:

10203040

### 7. isNaN()

The isNaN() method checks if a number is “Not-a-Number” (NaN).

Syntax:

isNaN(value)

For example:

console.log(isNaN(Number('hello'))); // Outputs: true
console.log(isNaN(Number(123))); // Outputs: false

### 8. isFinite()

The isFinite() method checks if a number is finite.

Syntax:

isFinite(testValue)

For example:

console.log(isFinite(143)); // Outputs: true
console.log(isFinite(Infinity)); // Outputs: false

### 9. parseFloat()

The parseFloat() method parses a string and returns a floating-point number.

Syntax:

parseFloat(value)

For example:

console.log(parseFloat("1.0230405060"));

Output:

1.023040506

## Conclusion

TypeScript is an enhanced version of JavaScript that simplifies working with numbers.
We’ve finished discussing how to use numbers in TypeScript, including both whole numbers and decimal numbers.

I hope this article has helped you understand the TypeScript Data Type “Numbers”.