You can likely take every public IP your organization has, run it through that, and see what your attack surface looks like. Very useful if you have an unmanageable and public computer network.
To do this on wan you need to run zmap which is considered mean.
On the other hand, if you have a small subnet, say, less than a /24, you might as well just nmap it yourself, and then you're also guaranteed to have the latest possible scan.