Number of people on the earth = 6.6 * 10^9
So that's (2^128)/(6.6 * 10^9) IPV6 addresses per person. That works out to approximately 5.1 * 10^28 addresses. That's a twenty nine digit number. That's a lot of IP addresses. To put that into perspective:
Number of IPV4 addresses available: 2^32
Number of IPV6 addresses per person: (2^128)/(6.6 * 10^9)
So that means that potentially every single person on the face of the earth could have ((2^128) ∕ (6.6 * (10^9))) ∕ (2^32) copies of IPV4. That's approximately 1.2 * 10^19 copies of IPV4 per person! Wow!