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The circumference of the Earth has been measured to be $40,075 \,\pu{km}$, which is only $21 \,\pu{km}$ from $40,096 = 2^{12}$. For reference, $40,075 \approx 2^{11.992}$. This is probably a strange coincidence, but originally a meter was set to be $1/10,000,000$-th of the distance from the North Pole to the Equator, so maybe there is a mathematical explanation.

Fred
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LMol
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2 Answers2

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Well, as others have pointed out we're a little off from $2^{12}$ kilometers. However, there is no coincidence that our world's circumference is close to $40000$ kilometers. From Wikipedia:

The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's circumference is approximately 40000 km.

Oscar Lanzi
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    Additional comment on this: another value that is not a coincidence is 21600=360*60 nautical miles, since the nautical mile originally measured a minute = 1/60 degree of latitude (or longitude at equator) – Max Xiong Apr 25 '22 at 18:34
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There's something wrong with your math, $2^{12} \ = \ 4096$:

$2^x \ = \ 40\ 000$

$\therefore x\log2 \ = \ \log\ 40\ 000$

$\therefore x \ = \ \frac{\log\ 40000}{\log\ 2}$

$\therefore x \ = \ 15.28771$

Thus, $2^{15.28771} \ = \ 40\ 000$

Federico
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Fred
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