No 'milliards de milliards' translates to billions of billions. So that would be 10^18
eta: From the article: "capable of managing dozens of petaoctets of data, in other words dozens of millions of gigaoctets"
10^18 bytes in petabytes = 888.17 petabytes
or basically a million terabytes if you round up.
basically 3 million 1TB hard drives in raid 5 (1M x 3). you can probably fit a 500 1TB 2.5" drives into a single rack if you really try, and 2,000 racks can fit easily into warehouse-sized facility. (grid of 100 x 20 racks)