Big Bang Theory: Sheldon's favourite number had secret hidden Jim Parsons meaning

After re-watching the series, a viewer was able to list different ways the number is held to esteem in Sheldon’s life.

Taking to the fan highlighted the significance of number 73. They wrote: “For starters, 1973 was the year that Jim Parsons was actually born.”

They added: “Sheldon loves the number thanks to its mathematical uniqueness.

“As he says ‘73 is the 21st prime number, Its mirror, 37, is the 12th and its mirror 21, is the product of multiplying 7 and 3… and in binary, 73 is a palindrome, 1001001, which backwards is 1001001.”