AD Computer Object Property ntsecuritydescriptor includes Owner
get-adcomputer -id <computerobject> -property ntsecuritydescriptor | select-object -expand ntsecuritydescriptor
Example:
PS C:\>get-adcomputer -id v2xen-15 -property ntsecuritydescriptor | select-object -expand ntsecuritydescriptor Path Owner Access ---- ----- ------ DOMAIN\join_user NT AUTHORITY\SELF Allow ...