$(function() 
  {
    $.ajax({                                      
      url: 'check.php',                  //the script to call to get data          
      data: "",                        //you can insert url argumnets here to pass to api.php
                                       //for example "id=5&parent=6"
      dataType: 'json',                //data format      
      success: function(data)          //on recieve of reply
      {
        var id = data[0];              //get id
        //--------------------------------------------------------------------
        // 3) Update html content
        //--------------------------------------------------------------------
        $('#count').html(id); //Set output element html
      } 
    });
    setTimeout(50000);
  });

</script>
<?php

/// how can I get javascript to only print a number? $counter = number; instead of being forced to use an #id and a div?
$counter = "<div id='count'></div>";

echo $counter;