The calculated distance (air line) between Sant Andreu de Llavaneres and Eixample is approximately 21 miles respectively 33 kilometers.
By car or train, the actual journey to Eixample is certainly longer, as only the direct route (as the crow flies) between Sant Andreu de Llavaneres and Eixample has been calculated here.
Air line (approximately)
33 kilometers
18 nautical miles