Two copies of your data will be stored in each AZ. If you have 4 AZs in your region then 2X4=8 copies of your data will be redundantly stored by Aurora
Aurora storage disk blocks are continuously scanned for errors and self healed.
Read Replicas supported:
Up to 15 Aurora Replicas (as opposed to only 5 MySQL read replicas)
Unlike MySQL read replica’s, Aurora Replicas support automatic failover