My guess is four propellers... She has four MTU:s with 12.000 hp each...!
Well I certainly did not see four screws in the link I posted above. However, since she has four MTU's it is a possibility? Maybe the fourth was unmounted in the image (if she does in fact has four) I think she may have four though because the 'middle' and 'right' screw looks centered and it would make sense if she had four.
I'd say four....outboard ones fwd, inboard ones aft, I think the one far right is just visible but the angles awkward. Shame those props are underwater, gorgeous looking things
(sorry, I'm a sucker for a sexy skewed screw)