You can confirm definitively by using telnet and specifying which port to connect to. From the command line run:
MyServer:~ Home$ telnet gateway.sandbox.push.apple.com 2195
Trying 17.149.34.143...
Connected to gateway.sandbox.push-apple.com.akadns.net.
Escape character is '^]'.
If there is an error connecting then it will just hang and not return - the above shows a working example where I can connect.
You'll need an SSH login to your hosting service to test it this way, and unfortunately you are unlikely to be able to test it without buying an account - so you probably have to rely on asking their customer services.
Be aware that basic hosting packages normally just provide an FTP login to let you serve up files, you'll usually have to pay extra to get a hosting package which provides SSH access (which you'll need if you are going to run code to connect to the Apple Push Notification Servers).
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