JSFiddle - React, Tailwind, and code Playground

HTML

<div id="texty" onmouseover="func1()" onmouseout="func2()">[email protected]</div>

JavaScript

var texty = document.getElementById('texty').innerHTML;
func1 = function() {
        if (document.getElementById('texty').innerHTML != '[email protected]') {
            document.getElementById('texty').innerHTML = '[email protected]';
        }
        else {
            document.getElementById('texty').innerHTML = '8 912 77 20 444';
        }
    };
func2 = function() {
       if (texty != '8 912 77 20 444') {
            texty = '8 912 77 20 444';
       }
       else {
            texty = '[email protected]';
        }
    };