In this example you can see to check given number wether pali or not.

palindrom_integer.js

/**
 * @param {number} x
 * @return {boolean}
 */
var isPalindrome = function(x) {
    let str = "";
    let digit = x.toString();
    for(let i = digit.length - 1; i >= 0; i-- ) {
        str += digit[i];
    } 
    str = Number(str);
 return x == str ? true : false;
};