No 6 gives his birthdate and time as 4.31 am, 19th March, 1928 - which is exactly the same as Patrick McGoohan's.
In this episode there is a sign stating "Questions are a burden to others; answers a prison for oneself."
We see several 'lava lamps'. While today we regard those as old style hippie cliche, when this was filmed the Astro Lamp had only been on the market for a few months. To most viewers at that time this was ultra-modern.
The rough cut of the first episode, "Arrival", was reportedly more than two hours long.
In an interview done on the set of Raiders of The Lost Ark, David Tomblin told author Derek Taylor that no one had ever made a penny out of the making of The Prisoner television series. When told by Taylor that the creators - Tomblin himself, Patrick McGoohan and the others - had made a work of art, Tomblin shrugged and said "That didn't pay any bills".