You probably won't be able to turn it at all with bare hands due to the sheer friction of the first few gear axles at the other end being amplified so much.
The friction of one wormgear is already enought to prevent rotation in the other direction. But with this many, impossible.
I also doubt if any of the gears except for the first ones rotate at all before the first gears are worn through, let alone before the battery to run out.