The calculated distance (air line) between Pekanbaru and Padangsidempuan is approximately 161 miles respectively 260 kilometers.
By car or train, the actual journey to Padangsidempuan is certainly longer, as only the direct route (as the crow flies) between Pekanbaru and Padangsidempuan has been calculated here.
Air line (approximately)
260 kilometers
140 nautical miles