Stephen Planck does some testing:
Regularly restoring test copies of your databases is the gold-standard proof that your backups work. Between those tests, however, RESTORE VERIFYONLY offers a fast way to confirm that a backup file is readable, that its page checksums are valid, and that the media set is complete. In this post you will see how to run that command from PowerShell by invoking SQL Server Management Objects (SMO), turning a one-off verification into a repeatable step you can schedule across all your servers.
Click through for the script and explanation. I also like dbatools’ Test-DbaLastBackup command, as that can also run RESTORE VERIFYONLY but goes further and allows you to restore the backup and then run DBCC CHECKDB against its contents.