How to use javascript var with # signature to point id ?

I tried to use `$("#test_input_val").remove();` as same as `$("#555").remove();` but not work.

<https://jsfiddle.net/L1dx3nLb/2/>

```
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $("button").click(function(){
    var test_input_val = document.getElementById("test_input").value;    
        $("#test_input_val").remove();
    });
});
</script>

<body>

<input id="test_input" value="555"/>
<div id="555">test test test test test</div>
<br>

<button>Remove div element</button>

</body>

```