The former Oasis star, who confirmed last year that he turned down an offer to join the panel, jested that he was drawn to the lucrative role.
"It's about six months' work, innit? I reckon it would have to be a million pounds after tax," he told Radio Times.
"I say that tongue-in-cheek. I don't really want to do it. But a million pounds for six months' work? That's good money if you can get it. Even I don't earn that much."
Gallagher revealed that Simon Cowell wanted him to be the "alpha male" of the refreshed X Factor panel.
The musician recalled: "He said, 'Basically [I want] somebody to replace me', and I was like, 'What, you mean have all the kids round my house in the back garden and saying to big lunatics, 'I've made my decision and I can only take three...' No, that's not going to happen in my house, the missus would kick off for a start'."
> Gary Barlow: 'I can't see Noel Gallagher on The X Factor'
Watch the video for 'AKA...What A Life' by Noel Gallagher's High Flying Birds below: