Balotelli moved to the San Siro from Manchester City in the transfer window and has since scored four goals in his first three games.
Galliani has said that the Italian striker's effect on the side is similar to that of former player Zlatan Ibrahimovic.
"Balotelli inspires the other players, sort of like the 'Zlatan Ibrahimovic effect'." Galliani is quoted as saying by Football Italia.
"He gives strength and his performances have a collateral effect on the others.
"His goals are proof we didn't just buy him for his media impact."
Balotelli will miss the Rossoneri's Champions League clash against Barcelona on Wednesday night as he is cup-tied.