"It will be an honour to play alongside all these great champions and I can't wait to get started," he told Sky Sport Italia.
"My hope is to start off straight away by winning the Italian Super Cup against Inter, my first official game for the club."
The Italy Under-21 international trequartista has an Italian mother and Egyptian father, earning him the nickname 'Little Pharaoh.'
"Adriano Galliani said El Shaarawy must take the place of Kaka and that filled his heart with pride," revealed agent Roberto La Florio.
"The lad is fired up to the max."