How many numbers 10 through 93 have the sum of their digits equal to a perfect square?

To find how many numbers from 10 to 93 have the sum of their digits equal to a perfect square, we first identify the possible perfect squares within the range of digit sums. The digit sum of a two-digit number ranges from 1 (for 10) to 18 (for 93). The perfect squares in this range are 1, 4, 9, and 16. By calculating the digit sums for each number from 10 to 93, we can determine that the numbers with digit sums equal to these perfect squares are 10-19 (sum = 1, 4, 9), and some others up to 93, yielding a total of 38 numbers.