使用strtotime将日期转换为秒

Given that code:

$date = '2014-05-22';

$number = strtotime($date);
$number2 = "143134652600";

echo $number;
echo $number2;
echo date('Y-m-d', $number);
echo date('Y-m-d', $number2);

Output:

1400709600
143134652600
2014-05-22
2014-05-22

Why $number is not equal to $number2?

and how to convert a Y-m-d '2014-05-22' to the same format as $number2 '143134652600'?

The output I get from that is:

1400731200
143134652600
2014-05-22 00:00:00
6505-10-03 20:43:20

I'm not sure how you get 2014-05-22 for both.