Convert from marathon to microinch

Unit Definition (marathon)
A long distance event based on an ancient Greek event, run over a distance of just over 26 miles.

Unit Definition (microinch)
The microinch is a common imperial unit of distance equal to one millionth of an inch, or 25.4 nanometers (nm). The microinch is used for precise machining tolerances and also to describe the roughness of surfaces.