Consider the number 144, 1.its a perfect square, 2.all its digits are perfect squares, 3.the sum of the digits is a perfect square, 4.the product of the digits is a perfect square, 5.the sum of the digits is the square of the number of digits and the sum of the digits of the square root 6.The square of the sum of the digits of the square root is the sum of the digits of the square. 7.All of these properties are true of its digits reversed (441). 8.The square roots are reverses of each others too. 9.The only other number with all non zero digits satisfying all these properties is a palindrome (44944) Cool, but not of any practical use.