Uncle Albert says the answer to his maths problem (3,465,222) is "a prime number of the Zeeman series". This is a fictional series, first used in Flash Gordon by Dr Zarkov who says: "A-ha! I thought it was one of the prime numbers of the Zeeman series." That it is fictional is reinforced by the fact that 3,465,222 is an even number and the only even Prime number is 2. Every other even number is a composite number, not a Prime.