JSFiddle - React, Tailwind, and code Playground

HTML

<button type="button" id="checkPalindrome">Check that it is Palindrome</button>

<input type="text" id="input">
    
<div>
    Is number a
    <a target="_blank" href="https://www.google.co.il/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CCoQFjAB&url=http%3A%2F%2Fwww.irisim.karmiel.k12.il%2Flearn%2Fmath%2Fhidot%2Fp-polindrom.doc&ei=LZA-VYy0KsfnaobjgKgE&usg=AFQjCNF_O4MsS0qdp5XLaxKoYE1uVFzJIw&sig2=pQjsVRY7SO4vy9Zs4o_Xwg&bvm=bv.91665533,d.d2s">Palindrome</a>?
    <span id="result">(result will be here)</span>
</div>

JavaScript

/* TODO: check if a number is a פילנדום on input's content change */
$("#checkPalindrome").click(function () {
    var input = $("#input").val();
    $("#result").text(isPalindrome());

});
function isPalindrome(S) {
    var array = input.split("");

    var i = 0;
    var j = array.length-1;

    while (i < j) {
        if (array[i] != array[j]) {
            return false;  
        } else {
            i++;
            j--;
        }
    }
    
    return true;
}