Convert from X unit to mile [international]

Unit Definition (X unit)
The X-unit (symbol xu) is a unit of length formerly used to measure the wavelength of X-rays and gamma rays. The X-unit is approximately 1.0021×10-13 metre. Defined by the Swedish physicist Karl Manne Georg Siegbahn (1886-1978) in 1925, the X-unit could not at that time be measured directly; the definition was instead made in terms of the spacing between planes of the calcite crystals used in the measuring apparatus.

Unit Definition (mile [international])
The mile is one of the most common measurements of distance. It originates from the Latin word for 1000, 'mille'. Originally a mile was the distance a Roman legion could march in 1000 paces. In medieval Britain, several mile units were used, including the modern mile defined as 8 furlongs (1609 meters). Note that French, Scottish and Irish miles varied from the English. In 1592, Parliament defined the statute mile to be 8 furlongs or 1609.344 meters.