Underscore.js _.isNumber() Function Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report Underscore.js _.isNumber() function is used to check whether the given object parameter is a number or not. If the given object is a number then it returns True value otherwise, it returns False. Syntax:_.isNumber( object );Parameters:object: This parameter holds the object element that needs to be checked whether it is a number or not.Return Value: It returns True if the given object is a number, and False otherwise. Example 1: This example shows the use of the Underscore.js _.isNumber() Function. html <!DOCTYPE html> <html> <head> <script type="text/javascript" src= "https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"> </script> </head> <body> <script type="text/javascript"> let arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; console.log(_.isNumber(arr)); let fun = function (element) { return element % 2 != 0; }; console.log(_.isNumber(fun)); let str = 'GeeksforGeeks'; console.log(_.isNumber(str.length)); </script> </body> </html> Output: Example 2: This example shows the use of the Underscore.js _.isNumber() Function. html <!DOCTYPE html> <html> <head> <script type="text/javascript" src= "https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"> </script> </head> <body> <script type="text/javascript"> console.log(_.isNumber(true)); console.log(_.isNumber(10)); console.log(_.isNumber('GeeksforGeeks')); console.log(_.isNumber(15.675)); </script> </body> </html> Output: Comment More infoAdvertise with us Next Article Introduction to JavaScript A ashokjaiswal Follow Improve Article Tags : JavaScript Web Technologies JavaScript - Underscore.js Similar Reads JavaScript Tutorial JavaScript is a programming language used to create dynamic content for websites. 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