Souzume Hachimangu Shrine (1861), Souzume, Northern Ward, Okayama City, Okayama Prefecture (05)


Problem

Find the length of one side of a cube that is $1881676371789154860897069 \ cubic \ inches$.


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Solution

When $1881676371789154860897069$ is decomposed into prime factors,

$$3^6×3607^3×3803^3=(3^2×3607×3803)^3. \qquad [*]$$

Therefore, the length of one side of the cube is

$$\sqrt[3]{1881676371789154860897069}=3^2×3607×3803=123456789.$$

 

$$(Answer) \quad 123456789 \quad inches.$$

 

 


$[*]$ The following high-precision online calculation site was used:

素因数分解 – 高精度計算サイト

 


Reference

Yoshikazu Yamakawa, ed. (1997) Okayama ken no Sangaku (Sangaku in Okayama Prefecture), p.27; pp.398-399.