Google owns and operates several largest or large data centers and Google's Largest data centers are usually all the same size.
Googles Largest data centers are located in areas including Dalles, Oregon; Atlanta, Georgia; Reston, Virginia; Lenoir, North Carolina; and Moncks Corner, South Carolina.
Google owns at least 12 largest data centers in the world to operate it's services and store all it's data that is on the internet.
The 12 large data centers are in the locations above.
Google also owns several other data centers in the world in other countries as well.
To keep Google.com up and Youtube.com up and running as well as store all the files and data and pull up the search queries etc it requires a lot of data centers that are scattered around the world.
Googles data centers are all over the world and they have millions of web servers to store all that information.