The TeamSpeak server is completely adjustable when it comes to ports. For a minimum default working of the server you need to open or forward the default port UDP 8767 (but even this port is adjustable to your needs). When you started the TeamSpeak server you can add servers running on other ports by either the webadmin or the TCPquery. To alter the webadmin port or the TCPquery port you need to edit the server.ini. The standard ports of these services are:
14534 for the webadmin
51234 for the TCQquery
So if you want to change these default ports, open and edit the server.ini (located in the map you installed TeamSpeak to).