cPanel offer two FTP servers to choose with. PureFTP and ProFTP - the default one is pure FTP. If you want to make a change, you can do this from WHM Main >> Service Configuration >> FTP Server Selection.
Change default FTP port for greater security for the server and to its contents, if the server is a shared one. Not only because the default port gives you a connection automatically and if they could guess the password, your content is in risk. So, I would suggesto to change the FTP port to a non standard one.