I think it is a very common experience among those who read this book to want to share it with family and friends. And it does appeal to both religious and non-religious people, although some people who are quite happy in their religious beliefs could dismiss it as irrelevant for them. On the other hand, if you know religious folks who are still searching for “something” more, they might be a perfect fit for the book. Sometimes, non-religious people are drawn to the book’s science, history, and cosmology and discover along the way that the book’s take on religion is a breath of fresh air.
In the end, The Urantia Book appeals most strongly to the truthseeker…that person who wants to know more about the purpose of life, about reality, about God, about Jesus, about life after death, and who are not afraid to step outside of their comfort zone to find that truth.
Keep in mind that this book is not exactly a casual read. You know your friends better than I do, so I would say that you should evaluate their possible interest with their personalities as you know them. I don’t want to discourage you, but I would advise you to be prepared to face rejection of your efforts.