I remember I really liked this movie when I was a teenager, along with the novel by Isaac Asimov that was based on the screenplay. (I never read the original story they based the screenplay on.) It was adventurous fun. I don’t recall if I was titillated by the presence on the cast of Raquel Welch, though they showed great restraint in having her covered up most of the time by the special submarine suit.
I wasn’t as impressed or entertained watching it this time around. I thought there were a couple of plot holes and, needless to say, the special effects weren’t up to the standards we are used to after all these years. But I would still recommend it if you are interested in early science fiction films or if you are watching with children, for it is certainly suitable for all audiences.