Random that takes two parameters doesn't work in Javascript [duplicate]

I'm a beginner in Javascript so I am currently attempting to code a random "machine" that takes a two parameters, tha minimal value and the maximal value, which the user types in an input="number", and displays a random number between those values, but the problem is that the random number doesn't display on the screen when I hit the button "Generate"

        <form>
            <div id="minimal_num">
                <label for="min">Minimal Value</label>
                <input type="number" name="min" required>
            </div>
            <p id="rnum"></p>
            <div id="maximal_num">
                <label for="max">Maximal Value</label>
                <input type="number" name="max" required>
            </div>
            <br style="clear: both;">
            <button id="generator" onclick="random_number()">Generate</button>
        </form>
    </div>
    <script type="text/javascript">
        function random_number() {
            document.getElementById("rnum").innerHTML = Math.floor(Math.random() * min) + max;
        }
    </script>