It would be 91 As 14^2=196 so two digit will be 28 *7 As 21^2=441 so two digit will be 63*7 So sum of digits=28+63=91

1st) 7 * 28 = 196 = 14*14 2nd) 7*63 = 441 = 21*21

28+63=91

Answer is 91

A five-digit number is formed using digits 1,3,5,8 and 9 without repeating any one of them. What is the sum of all such possible numbers?