Iniciando o Hoje

Como eu sempre esqueço, melhor salvar logo essa função. Transformando milissegundos em Horas.

  function tempo($time_to_convert){
  
    $elapsed_hours = floor($time_to_convert / 3600000);
    $remaining = $time_to_convert - $elapsed_hours * 3600000;
    $elapsed_minutes = floor($remaining / 60000);
    $remaining = $remaining - $elapsed_minutes * 60000;
    $elapsed_seconds = floor($remaining / 1000);
    $remaining = $remaining - $elapsed_seconds * 1000;
    $elapsed_fs = floor($remaining / 10);
    
    $hours = ($elapsed_hours < 10) ? "0$elapsed_hours" : $elapsed_hours;
    $minutes = ($elapsed_minutes < 10) ? "0$elapsed_minutes" : $elapsed_minutes;
    $seconds = ($elapsed_seconds < 10) ? "0$elapsed_seconds" : $elapsed_seconds;
    $hundredths = ($elapsed_fs < 10) ? "0$elapsed_fs" : $elapsed_fs;
    
    return "$hours:$minutes:$seconds:$hundredths";
  }