How many people could stand on the surface of the earth?

Question

without any physical or natural obstructions?

Answer 1

548, 965,849,342.6 if nobody farts.

Answer 2

10trillion

Answer 3

I once heard [about 10 years ago] that the entire population of the world [back then] could stand inside the borders of the state of Rhode Island without being able to touch each other with their arms stretched out.

Answer 4

the proportion of the current population that doesn't prefer to sit