Another solution. Go to Organisation/Overview. Make sure "Hide table" is not ticked. Click on the arrow to expand the table. Go to the Devices tab. Click on the + to add the columns "Public IP" and "Uplink IP (Port 1)". You can add the second port as well if you want.
Search for MX.
![Screenshot from 2018-09-20 16-37-38.png Screenshot from 2018-09-20 16-37-38.png](https://community.meraki.com/t5/image/serverpage/image-id/4443i41FB2EC2556535DE/image-size/large?v=v2&px=999)