JSFiddle - React, Tailwind, and code Playground

JavaScript

var fact = 1;
    for (var i = 100; i > 0; i--) {
        fact *= i;
    }

    var summed = 0;
    while (fact > 0) {
        summed += Math.floor(fact % 10);
        fact = fact / 10;
    }

    alert(summed);