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Comment by trehalose | Hacker News Reader

> Try multiplying a billion billion billion billion by a trillion trillion trillion trillion, then multiply that by a thousand, and that (10 to the 31st power) is the mind-numbing estimate of how many individual viral particles are estimated to populate the planet.

What definitions of "billion" and "trillion" are they using? 10 to the 31st would be only ten million trillion trillion, going by the common definition of million as 10 to the 6th and trillion as 10 to the 12th.

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Yeah, if you multiply "a billion billion billion billion by a trillion trillion trillion trillion, then multiply that by a thousand" you get a larger number than the atoms in the observable universe.

That’s a lot of viruses! I’m staying inside.

  4 x 9 + 4 x 12 + 3 = 87 
  4 x 3 + 4 x  4 + 3 = 31.

That’s the only genesis of this error I could come up with - somehow they associated billion with 3 and trillion with 4 (conceivably because “N-illion” = 1000^(N+1) [1], and then forgot about the factor of three embedded in the base of 1000).

[1] in the US system. In Germany and historically the UK, apparently, it’s 1000,000^N = 1000^(2N), which I personally prefer.

In germany the step size is twice as large; million, milliard, billion, billiard, etc. Makes things neater IMO.

FWIW, the article has been corrected now to read:

> Try multiplying a billion by a billion, then multiply that by ten trillion, and that (10 to the 31st power) is the mind-numbing estimate of how many individual viral particles are estimated to populate the planet.

(I can't find a "correction" notice... It's Stanford Medicine, not a proper newspaper.)

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