If it looks stupide but it works…

555 95472, or 5 for short, was boy close in age to Charlie Brown. 5 had brown spiky hair, and he wore an orange shirt with the number 5 on it. 5 also played for Charlie Brown’s baseball team. 5 was given a numerical name by his father, who was upset over the preponderance of numbers in people’s lives; when questioned, 5 clarified that this was not his father’s way of protesting, it was his way of “giving in.” 5’s family are named 1 (father), 2 (mother), 3 & 4 (twin sisters). and 6 (sister). His last name, 95472 (the accent is on the 4), was taken from the family’s ZIP code; it is also the zip code for Sebastopol, California, where Schulz lived at the time.

From Wikipedia.

Martha Wells. ‘Death of the Necromancer’ is a stand alone. Thief and his actress mistress are on a course of vengeance, get side tracked by evil. ‘The Wizard Hunters’ is the first book of a follow up trilogy featuring their daughter. First book is 1890’s tech plus magic, and the trilogy is WW1 level tech. Airships and ocean liners.