24 hours? Your database must be well over 1 TB or your hardware is very outdated.
If you compress backup, try to estimate its size + 20%, make sure that you have enough space to hold backup file. This is most likely the reason why your backup failed at the end.
Monitor backup progress from sys.dm_exec_requests view.
For future: partition your database, set old partitions to read-only, make one full backup, and then do partial backups on read-write filegroups. This will drastically reduce your backup space, time, resources.