cPanel relies and operates on the selected ports by default for the services which runs on cPanel.
The following below is the common ports used by cPanel for the services which is available from cPanel and services offered.
NON-SSL Enable
Webmail
http://domain_name:2095
http://domain_name/webmail
Control Panel
http://domain_name:2082
http://domain_name/cpanel
WebHost Manager (WHM)
http://domain_name:2086
http://domain_name/whm
SSL Enabled
Webmail
http://domain_name:2096
https://domain_name/webmail
Control Panel
http://domain_name:2083
https://domain_name/cpanel
WebHost Manager (WHM)
http://domain_name:2087
https://domain_name/whm