var birth = new Date(1977, 3, 1, 5, 40, 26);

function format(number) {
  var input = number.toString();
  var output = ' с';
  var spaces = Math.ceil(input.length / 3);
  for(var i = 0; i < spaces; i++) {
    output = ' ' + input.substr(input.length - (i * 3), 3) + output;
  }
  output = input.substring(0, input.length - ((i -1)* 3)) + output;
  return output;
}

function range() {
  return Math.round((new Date() - birth) / 1000);
}

window.onload = function() {
  // var td = document.getElementsByTagName('td').item(0);
  // var div = document.createElement('div');
  // td.insertBefore(div, td.firstChild);
  var div = document.getElementById('timer');
  var text = document.createTextNode(format(range()));
  div.appendChild(text);
  setInterval(function() {
    text.nodeValue = format(range());
  }, 1000);
}