The calculated distance (air line) between An Nu‘mānīyah and Ḩalabja is approximately 184 miles respectively 296 kilometers.
By car or train, the actual journey to Ḩalabja is certainly longer, as only the direct route (as the crow flies) between An Nu‘mānīyah and Ḩalabja has been calculated here.
Air line (approximately)
296 kilometers
160 nautical miles