Depends on a license.
With a basic license, you can have a total of 10 IPSec (Site to Site or Remote Access) connections, any combination).
With a Security + license, you can have a total of 25 IPSec connections, again any combination of Site to Site or Remote Access.
SSL VPN licenses are purchased separately. Out of the box you get 2 licenses (with Basic or Security + appliance license). You can raise this up to a maximum of 25 SSL VPN licenses.
Note that even with 25 SSL VPN licenses, you can not exceed a maximum total of 25 VPN connections, no matter the combination of IPSec Site to Site, IPSec Remote Access, or SSL VPN.
So out of the box, a Basic license unit can have 10 IPSec VPN connections. 2 of those 10 can be SSL VPN connections, unless you purchase additional SSL VPN licenses. For the Security + appliance license, you get a total of 25. 2 of those 25 can be SSL VPN unless you purchase more SSL VPN licenses.
I hope that's clear...