The calculated distance (air line) between Jettingen-Scheppach and Illertissen is approximately 19 miles respectively 31 kilometers.
By car or train, the actual journey to Illertissen is certainly longer, as only the direct route (as the crow flies) between Jettingen-Scheppach and Illertissen has been calculated here.
Air line (approximately)
31 kilometers
17 nautical miles