What is the maximum size of a number that can be stored in an Integer variable?

In PHP, the size of a number that can be stored in an Integer variable depends on the system architecture:

• On 32-bit systems, the maximum Integer value is usually 2³¹ - 1 (2147483647).
• On 64-bit systems, the maximum Integer value is usually 2⁶³ - 1 (9223372036854775807).

Example of checking the maximum value:

<?php
echo PHP_INT_MAX;
// Outputs the maximum integer value for your system
?>

If the number exceeds this limit, PHP automatically converts it to a float type.