The calculated distance (air line) between San Martín Azcatepec and Iztapalapa is approximately 24 miles respectively 38 kilometers.
By car or train, the actual journey to Iztapalapa is certainly longer, as only the direct route (as the crow flies) between San Martín Azcatepec and Iztapalapa has been calculated here.
Air line (approximately)
38 kilometers
21 nautical miles