Hi Rajendra,
Regarding default port used by Max db, for your specific confiuration, you can check which port is being used by this process -
Go to Run -> drivers, Go to etc folder and check for services file.
As per Max DB documentation, different ports used for Max DB are -
http://maxdb.sap.com/doc/7_7/44/bbddac91407006e10000000a155369/content.htm
For username/password thing, here is the answer for that -
http://maxdb.sap.com/doc/7_7/44/bbddac91407006e10000000a155369/frameset.htm
Hope this helps,
Regards,
Ashutosh