The calculated distance (air line) between Šentilj v Slov. Goricah and Velenje is approximately 34 miles respectively 55 kilometers.
By car or train, the actual journey to Velenje is certainly longer, as only the direct route (as the crow flies) between Šentilj v Slov. Goricah and Velenje has been calculated here.
Air line (approximately)
55 kilometers
29 nautical miles