Technically you are right, but I am after a string which I can just cut off at some point and insert a decimal dot, so I am flexible.
The point of the exercise is for printing, into LaTeX. That is, I want to generate output like raw"$4.92 \cdot 10^{-3}$"
and raw"$22.71 \cdot 10^{6}$"
(engineering notation).