What is confusing about it?Now, I have found this:
where it says:
satis: Satis ("enough") does not function as an adjective in Latin, but as a noun, and therefore, does not agree with a noun, as the English adjective enough does, e.g. enough money. Instead, Latin uses the genitive case after satis to complete its meaning, e.g. satis pecuniae, "enough (of) money." This type of genitive is called a partitive genitive, another important use of this case in Latin. Like nihil (Chapter 4), satis is indeclinable.
...which leaves me more confused!
I totally agree with that explanation.
The OLD too, by the way, only classifies satis as a substantive and an adverb.