Quote from: bob123 on December 16, 2017, 09:00:41 AM

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there are 2^256 public keys and 2^160 addresses,
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2^160 is about 1,460,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000.
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Or precisely:
1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976

Quote from: Kwothe117 on December 16, 2017, 01:59:28 AM

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Also, roughly how many public addresses are currently storing bitcoin?

Quote from: aplistir on December 16, 2017, 07:29:12 AM

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About 2 months ago there were:
~21600000 addresses containing some balance and
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Note that there could NEVER be more than 2,099,999,997,690,000 addresses storing bitcoins at any moment in time.

Furthermore, due to lost bitcoins and some addresses storing more than 0.00000001 BTC, the actual maximum number of addresses that ever WILL store bitcoins at any given moment in time will ALWAYS be SIGNIFICANTLY less than 2,099,999,997,690,000 addresses.

Therefore, the absolute worst case scenario (an imaginary situation where there actually are 2,099,999,997,690,000 addresses storing bitcoins) would result in less than:
0.0000000000000000000000000000002 % of the available address space being used to store bitcoins at any moment.