Can any computer connected to the Internet connect to the SSH server using the phone's IP address?
depends on how your ssh server is configured, along with TCP wrappers. By default, that is typically yes. However you can restrict who and from where can successfully connect via SSH by editing
/etc/hosts.allow and changing
SSHD : ALL : ALLOW
to something more restrictive. There is also
/etc/hosts.deny you can play with, along with editting
/etc/ssh/sshd_config. Realize SSH is the protocol and is completely independent of the computer system... if my dell laptop follows the SSH protocol and a coke machine follows the same version of the SSH protocol, then a valid communication link can be established between the two... over TCP/IP. When this will not work is when that communication is blocked via some other means. Not to mention firewall settings...
How can I find out if the IP address is a public IP address for the phone's network interface.
use a browser on the phone and go to a website that will report back to you the [public] ip address it sees your phone as. If that reported address matches what is in Phone_Settings, then that would be a yes. But I can tell you what ip address your phone settings is saying is not a public ip address, for the same reason my home computer through the comcast modem gives my home computer 10.0.0.1. Simply web search
what is my public ip to find any of a hundred sites that will tell you your public IP.
unix&linux > AndroidEnthusiasts :)