There are more ways to arrange a deck of cards than atoms on Earth

Wait! How many atoms are on Earth?!?

First it blows me away that ‘we’ know the number - but does ON Earth mean the Earth itself, everything on the surface, and things in the atmosphere?
Or is it just things on the surface?

Whatever the case; What’s the number?

Also, I apparently totally don’t comprehend the size/weight of an atom becaue Id’ve guessed there were 80,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 atoms in my couch.