Depending on the model AP, the max # of APs within an RFDomain (without a site controller) will vary.
Of those you list though, the 7632 will support up to 256 APs in an RFDomain (with the latest version of WiNG code, 5.9.1+)
If all 4 of these AP models are in the same RFDomain, then the answer is that you can have up to 256 APs in the RFDomain (if running the latest versions of WiNG)
Just FYI though, for the AP650's, the last version of WiNG code is 5.8.6.9. In this case, you would not be able to run the 7632, 7532, and 7522 on 5.9.1 and the 650 on 5.8.6.9 at the same time...within the same RFDomain.
If you decided to just upgrade all APs to the latest version supported by the AP650, then the most APs you could have in 1 RFDomain would be 128 APs.
