In the number 58746932, if a digit is a prime number, add 2 to that digit, and if it is a non-prime number, subtract 2 from that digit. How many digits are repeated exactly twice in the final transformed number?

If 1 is subtracted from each odd digit and 2 is subtracted from each even digit in the number 5473629, what will be the sum of the digits which are third from the left and third from the right in the new number thus formed?

If 2 is added to each odd digit and 1 is subtracted from each even digit in the number 58637124, how many digits will appear more than once in the new number thus formed?