JSFiddle - React, Tailwind, and code Playground

JavaScript

function factorizar(n) {
    var i = 2, res = [];
    
    while(i <= n) {
        if(n%i && i++) continue;
        
        n = n/i;
        res[i] = res[i] || 0;
        res[i]++;
    }
        
    return res.reduce(function(memo, current, index) {
        memo.push(
            index + (current > 1 ? '^' + current : '')
        );
        return memo;
    }, []).join(' x ');
}

document.write(
    '1024: ' +
    factorizar(1024) +
    '<br />'    
);

document.write(
    '1025: ' +
    factorizar(1025) +
    '<br />'
);

document.write(
    '16: ' +
    factorizar(16) +
    '<br />'
);