gmail account hacked...

On 24-1-2014 my google account hacked and the hacker changed the password and enable 2-step verification into my account by adding his own mobile number.
Now is it possible to get back into account bcoz the hacker is changing my all information on network i registered and changing payment info etc.
plz help me anyway to get back into my account…

Contact google here is the number 1 (650) 253-0000

i can give you back.
just contact me here
[email protected]