A HiOS 3A device maximum supports 30 areas of which one is the backbone area 0.0.0.0, a HiOS 3S device supports 15 areas. This means you can create 29 or 14 areas other than the backbone area within a device.
Creating a second area makes the device to an Area Border Router ABR.
Please note that each area needs CPU performance.
Please also remember what an area is for and evaluate whether it's necessary to have several areas.