convert media_id for url

convert.php

<?php
function instagram_id_to_url($instagram_id){

		$url_prefix   = "https://www.instagram.com/p/";
		$parts        = explode('_', $instagram_id);
		$instagram_id = $parts[0];
		$userid       = $parts[1];
		$alphabet     = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_';
		while($instagram_id > 0) {
			$remainder    = $instagram_id % 64;
			$instagram_id = ($instagram_id-$remainder) / 64;
			$url_suffix   = $alphabet{$remainder} . $url_suffix;
		};
		return $url_prefix.$url_suffix;
	}
  $insta_id = "1596473034378028188_5929846787";
$t = instagram_id_to_url($insta_id);