Here's a breakdown of the components:
* Que: This is a Spanish word meaning "that" or "what".
* Gato: This is the Spanish word for "cat".
* Hummmmmmm: This is an onomatopoeia for a humming sound, usually made by a person or a machine.
Since the phrase doesn't make grammatical sense in Spanish, it's safe to assume it's not intended to be a serious statement.
To understand the intended meaning, you would need more context. For example:
* Is it a joke? The person might be making a funny observation about a cat that's humming.
* Is it a meme? The phrase could be a meme that has a specific meaning within a particular online community.
* Is it a misheard lyric? Perhaps it's a misspelling of a song lyric, and the actual meaning is something different.
Without more context, it's difficult to say what "que gato hummmmmmm" means.