On the Show, Sheldon’s favorite number is 73, because 73 is the 21st prime number. Its mirror, 37, is the 12th and its mirror, 21, is the product of multiplying 7 and 3. In binary 73 is a palindrome, 1001001, which backwards is 1001001. In real life, Jim Parsons, who plays Sheldon was born in… Continue reading Significance of number 73 from Big Bang Theory