NSA is the largest employer in Maryland. In 2020 it supposedly has a 62.7 billion dollar budget they deign to tell us about. The number of employees are classified, but it is estimated to be 30,000-40,000.
In 2017 Homeland security estimated a border wall would cost 21 billion dollars to build.
FReegards
The NSA’s budget is actually scattered cross the globe. The NRO primarily funds many of the sensor systems used to feed the NSA. So, combined, they have a huge budget that is scattered primarily within the USAF but also consumed by all DoD departments and government agencies.