如何将网址（Numbers）更改为字母单词？

This might be a very basic question.

I have bought space from a web supplier. They have given me a url which is numbers like http://107.170.253.5/. I wondered how can I change it to an alphabet link such as myfirstwebsite.com.au.

Appreciate any suggestion...

Make use of gethostbyaddr() in PHP:

//Get the Internet host name corresponding to a given IP address
<?php
$hostname = gethostbyaddr('107.170.253.5');
echo $hostname; //<---- To print the hostname

Edit:

This is not working. it is giving me a link to my wireless!

That actually works, you have not mapped your domain with the IP address. See the below example and it works perfectly:

<?php
echo $ip = gethostbyname('www.stackoverflow.com'); //"prints" 198.252.206.140
echo gethostbyaddr($ip); //"prints" stackoverflow.com