HTML

<!--css-->
<link rel="stylesheet" type="text/css" href="jquery.datetimepicker.min.css">

<input type="text" id="input">
<div id="calendar" style="display: none;"></div>

<!--javascript-->
<script src="https://code.jquery.com/jquery-1.12.4.min.js"></script>
<script src="jquery.datetimepicker.min.js"></script>

JAVASCRIPT

$(document).ready(function(){
    $('#calendar').datetimepicker({
        date: new Date(),
        viewMode: 'YMDHMS',
        onDateUpdate: function(){        
            var year = this.getText().slice(0,4);
            var month = this.getText().slice(5,7);
            var day = this.getValue().toString().slice(0,3);
            var date = this.getText().slice(8,10);
            var hour = this.getText().slice(11,13);
            var minute = this.getText().slice(14,16);
            var second = this.getText().slice(17,19);

            $('#input').val(year + '-' + month + '-' + date + ' ' +
                            day + ' ' + hour + ':' + minute + ':' + second);
        }
    });

    $('#input').click(function(){
        $('#calendar').fadeIn(200);
    });

    $('table.buttonpane > tbody > tr > td.ok').click(function(){
        $('#calendar').fadeOut(200);
    });
});

REFERENCE

  1. 'jquery.datetimepicker.min.js', 'jquery.datetimepicker.min.css' 다운로드 링크