Finding Hostname of MySQL installed on AWS

I am not able to figure out hostname of my MySQL database which is installed on AWS T2 micro server. I can connect via phpmyadmin. And connecting via php code as localhost works ok too. However can't find hostname or ip which is needed to connect it from service hosted on other server (where localhost won't be an option)

Tried running following SELECT variable_value FROM global_variables WHERE variable_name = 'hostname' However the output is ip-172-31-23-11. This doesn't work as hostname when I try to connect.

Please help.