Here's some interesting notes about this third book of the Torah. The original title of the book is "In the Wilderness", but the English Bible has it as "Numbers", likely due to the beginning of the book having a census. Numbers do play a role in the book, but the real story of is the travelling of the Israelite nation from Mt. Sinai through the wilderness, to the Promised Land. The Hebrew title makes more sense. This book includes pieces of narrative (story), intermixed with pieces of law - instruction for assembling and caring for the Tabernacle, rules for cleanness, and such.
Geneaology is important to the ancient Hebrews, hence their recording of details of who was related to who, and who was supposed to do what is an important historical document.
In chapter one, verse 46 it says that there were 603,550 men above the age of twenty, able to bear arms, from twelve tribes (not including the tribe of Levi - they were dedicated to guarding and serving the Tabernacle); Jewish commentators note that according to legend, there are 603,550 letters in the Torah - "Just as the absence of one letter renders a Torah scroll unfit for use, the loss of even one Jew prevents Israel from fulfilling its divine mission."
Chapter five includes an odd piece of legislation concerning a husband who suspects his wife has been unfaithful to him, but he is unable to prove it. In reading this account, it may come across as demeaning to the woman. Understanding context reveals it to be a brilliant piece of law designed to protect the right of the woman (in a day and age when women were often unprotected and very vulnerable). If the man suspects his wife, without proof, the lawcourts will not be helpful to him; there needs to be some authoritative way to settle the issue. By taking the wife to the priest, and having her drink some water that will only have an effect if she has been unfaithful, the assumption is that she is not guilty.