The calculated distance (air line) between Pervomayskiy and Novosibirsk is approximately 156 miles respectively 250 kilometers.
By car or train, the actual journey to Novosibirsk is certainly longer, as only the direct route (as the crow flies) between Pervomayskiy and Novosibirsk has been calculated here.
Air line (approximately)
250 kilometers
135 nautical miles