<?php

$number = "123.00";
echo ($number == (int) $number) ? (int) $number : $number, PHP_EOL;
// 123

$number = "123.10";
echo ($number == (int) $number) ? (int) $number : $number, PHP_EOL;
// 123.10

$number = "123.1000";
echo ($number == (int) $number) ? (int) $number : $number, PHP_EOL;
// 123.1000