Google is one of the biggest cloud storage providers in the world. With more than 2.5 billion active Android devices, the advertising and search giant has to allocate potentially up to 20 Exabytes (assuming a ratio of two devices per user account); that almost 20 billion GB of data as each Gmail account is tied to a 15GB free cloud storage tier.
That’s a lot of hard disk drives and a lot of servers (probably more than a million) spread over the world.