How long lasts the copyright over a book? Is there a way to check the current copyright status of a book by using ISBN?
ISBN does not give information about the copyright status of the book: ISBN numbers are just identifiers, and publishers buy them in bunches.
For books published after 1978, copyright usually extends until 70 years after the death of the last author of the book: some nation may have different durations, however. As for books published before 1978, it depends from where you are located. Wikipedia has some information, but you should better check your local laws.