You can uninstall or removes an installed cen64 package itself from Ubuntu 16.10 (Yakkety Yak) through the terminal,
$ sudo apt-get remove cen64
If you would like to remove cen64 and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove cen64
If you use with purge options to cen64 package all the configuration and dependent packages will be removed.
$ sudo apt-get purge cen64
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove cen64