Minecraft World stats

Minecraft World: 60000001*256*60000001 (X*Y*Z) placeable blocks in size (Total count of 921,600,061,120,000,000 blocks, thats over 921600 times a TRILLION!, pronounced 9 hundred & 21 quadrillion, 6 hundred trillion, 61 billion & 120 million. The overworld/end/nether (2 of either) makes it 1,843,200,122,240,000,000 blocks total, and the overworld, nether, and end combined makes it 2,764,800,183,360,000,000, also quintillion cones after quadrillion, which is after trillion, also if all dimensions were filled with chests, it would be able to store 4,692,084,714,146,080,000,000 blocks (if you have them in stacks of 64, and chests in a checkerboard design)

1 layer (Horizontal): 3,600,000,120,000,000; 3 quadrillion, 6 hundred trillion, ane 1 hundred & 20 million.

Of course, all of this assumes there are air blocks in every position of said world(s), and you are using 1x1x1 blocks, not beds or sunflowers.