SSL on port number

Hello, Several times now I need to issue SSL for requests on HTTPS on certain port numbers for certain web-based applications, I think that it cannot be done, however, nonetheless, I would like to ask if it is possible somehow and if yes, how. To explain further, let's say I have an application that is working on test.com:3000 Is there any way to SSL secure test.com:3000 without removing the port with an .htacccess file, the domain should remain available on test.com:3000 and not test.com only. Any guidance on this will be highly appreciated.