The average menstrual cycle length -- that would be from the first day of your period until the next period begins -- is said to be 28 days. There's a misconception that anything shorter or longer than 28 days is not normal, but this isn't true. A cycle as short as 21 days or as long as 35 days is considered normal.
Columbo's first name is never explicitly revealed in the series. However, when Columbo flashes his badge in the episode Dead Weight (Season 1 Episode 3), the name 'Frank' can clearly be seen on his ID. In the german DUB befriended police detectives occasionally call him Frank. The answer is no.
Each episode featured a well-known character actor or minor star as the murderer. Robert Culp and Jack Cassidy had the highest number of returns as guest villain (three each). Columbo won seven Emmys over the first run of the series, including three for Falk and one for the series itself. Columbo spawned only one spin-off, NBC's short-lived, Mrs. Columbo (name later changed to Kate Columbo, Kate the Detective, and Kate Loves a Mystery) with Kate Mulgrew in the title role.