从mysql数据库回显错误的日期

May be is really silly and newbie question but I have date saved in database like this: 2016-05-06 06:13:52 Then I echoed date on the page like this

date('F j, Y', $row['start_datetime'])

but instead to get date like May 06, 2016 i've got printed date -> December 31, 1969.. How is this happen? From where I got December 31, 1969?

date('F j, Y', strtotime($row['start_datetime']));
$date = new \DateTime($row['Date']);
$date->format('F j, Y');