<form target="_blank"> <input type="number" max="44" /> <button type="submit">Попытаться отправить</button> </form>
var div = document.getElementById(Id дива );
var max = div.getAttribute("innerHTML");
var max = div.innerHTML;
<div id="div">44</div> <script> var max = +document.getElementById('div').innerHTML; var max2 = document.getElementById('div').innerHTML; alert(max + 2); alert(max2 + 2); </script>