Javascript has some limitations regarding numbers. Any number should be in a standardized computer network format. If any integer violates this rule, it can't be a safe integer.
The safe integers consist of all integers from -(2^53 - 1) inclusive to (2^53 - 1) inclusive (± 9007199254740991 or ± 9,007,199,254,740,991). Whether to know the given number is a safe integer or not, Number.isSafeInteger() must be used.
syntax
Number.isSafeInteger(num);
This method takes a number as a parameter and evaluates whether the number is in the range of safe integer or not. If the provided number is in the range then true will be displayed as the output else false will be displayed as the output.
Example-1
In the following example, the provided two numbers are in the range from -(2^53 - 1) inclusive to (2^53 - 1). So the Number.isInteger() method has evaluated the numbers as true.
<html>
<body>
<script>
var u = Number.isSafeInteger((Math.pow(2,53))-1);
var res = Number.isSafeInteger(-1);
document.write(res);
document.write("</br>");
document.write(u);
</script>
</body>
</html>Output
true true
Example-2
In the following example, the provided number is not in the range from -(2^53 - 1) inclusive to (2^53 - 1). So the Number.isInteger() method has evaluated the number as false.
<html> <body> <script> var u = Number.isSafeInteger(-(Math.pow(2,53))-5); document.write(u); </script> </body> </html>
Output
false