PHP

php is numeric

//is_numeric — Finds whether a variable is a number or a numeric string
is_numeric ( $variable ); // returns true or false

php is variable a number

if(is_numeric($what_am_i)){
	//true
}  

php is int

is_int(mixed $value): bool

php is_int

<?php
$values = array(23, "23", 23.5, "23.5", null, true, false);
foreach ($values as $value) {
    echo "is_int(";
    var_export($value);
    echo ") = ";
    var_dump(is_int($value));
}
?>
  
/* Output
is_int(23) = bool(true)
is_int('23') = bool(false)
is_int(23.5) = bool(false)
is_int('23.5') = bool(false)
is_int(NULL) = bool(false)
is_int(true) = bool(false)
is_int(false) = bool(false)
*/