The following table, obtained displays a general list of which programs and network services access which ports. Many services/programs can access any port. As a general rule, ports below 1,024 are reserved for system use. The maximum port number is 65,536. Any port can be used by hackers if there's a trojan on the system or if networking is enabled on the system.
 

For a comprehensive list of ports and the services using them, in text format, use the following download.