- date_diff: documentation ( source)
- var_dump: documentation ( source)
- date_create: documentation ( source)
<?php
$min = \date_create('@' . PHP_INT_MIN);
var_dump($min->format('Y-m-d H:i:s'));
$max = \date_create('@' . PHP_INT_MAX);
var_dump($max->format('Y-m-d H:i:s'));
$diff = \date_diff($min, $max);
echo $diff->format("%R%a days");