How secured is the network from outside world?

It is assured without doubt that things don't seem the way they are. My routers web interface was configured in a way I wanted, only to find that it has least changed the priorities. For instance the WAN interface and LAN interface was changed but the nmap output for open port is pretty evident.
PORT     STATE SERVICE
21/tcp   open  ftp
23/tcp   open  telnet
80/tcp   open  http
5431/tcp open  park-agent
This is how I configured the router

Not only that the TR-069(technical report) client config for ACS (auto configuration servers)was enabled all the time in the CPE(customer premises equipment). This enabled the ones who provided the device to carry out the so called upgrades(I sincerely doubt that)  in my device.  

In short the only protection that is there is because of the dynamic IP address that is allotted to the user...