What type is NaN in js

NaN in JavaScript stands for "Not-a-Number", which is a special data type used to represent values ​​that cannot be represented as numbers. It is a reserved word whose type cannot be determined using the typeof operator and is often produced when performing mathematical operations on non-numeric strings or invalid input. NaN cannot participate in mathematical operations. Any operation performed on NaN will return NaN. You can use the Number.isNaN() function to detect NaN.

#What is NaN in JavaScript?

NaN, which stands for "Not-a-Number", is a special data type in JavaScript, used to represent values ​​that cannot be represented as numbers.

Details:

• NaN is a reserved word and the only one in JavaScript whose type cannot be determined using the typeof operator special value. typeof NaN will return "number", but NaN is not actually a number.
• NaN is often generated when performing mathematical operations on non-numeric strings or other invalid input. For example:

<code class="javascript">const result = parseInt("abc"); // NaN
const result = 10 / "hello"; // NaN</code>

• NaN cannot participate in mathematical operations. Any mathematical operation on NaN returns NaN:

<code class="javascript">console.log(NaN + 10); // NaN
console.log(NaN * 5); // NaN</code>

• NaN can be detected with the Number.isNaN() function. This function takes NaN as an argument and returns a boolean value:

<code class="javascript">console.log(Number.isNaN(NaN)); // true</code>

Important:

• NaN is not a number, even though typeof NaN returns "number".
• NaN cannot participate in mathematical operations.
• Use the Number.isNaN() function to detect NaN.

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