Ubuntu Server 16.04 Uninstall Apache2

 Follow these steps to remove the apache2 service using Terminal:

1. First stop the apache2 service if it is running with: sudo service apache2 stop

2. Now remove and cleanup all the apache2 packages with:

   sudo apt-get purge apache2 apache2-utils apache2.2-bin apache2-common
   //or 
   sudo apt-get purge apache2 apache2-utils apache2-bin apache2.2-common
   

3. Finally, run sudo apt-get autoremove just in case any other cleanup in needed

You can do the following two tests to confirm apache has been removed:

1. which apache2 - should return a blank line
2. sudo service apache2 start - should return apache2: unrecognized service