ekistic units

anthropos – 1
room – 2
house – 5
housegroup – 40
small neighborhood - 250
neighborhood – 1,500
small polis – 10,000
polis – 75,000
small metropolis – 500,000
metropolis – 4,000,000
small megalopolis – 25,000,000
megalopolis – 150,000,000
small eperopolis – 1,000 million [1,000,000,000]
eperopolis – 7,500 million [7,500,000,000]
ecumenopolis – 50,000 million [50,000,000,000]