I believe there were only two or three brothels in the entire state. They also were restricted by county and pretty much way out in the boonies. At least one has closed and it is possible that only one continues to exist in the state.
Apparently I am mistaken. A listing of current and closed brothels in NV reports 49, most seem to be called some kind of ranch. Do know that it is illegal in Clark County, where Las Vegas is. No I don't know how many are closed other than Mustang Ranch!
Found it eight are closed and only permitted in two counties, Storey and Lyon. Leave out Reno as well as Las Vegas!