9,999,876 is the greatest seven-digit number using four different digits.
1324
987654
7,543
.961
9,999,876 is the greatest seven-digit number using four different digits.
1324
987654
To be an even number then the final digit = 2. The largest single prime digit is 7 (as both 8 and 9 are composite). The greatest even number fulfilling the conditions is 77777772.
7,543
Proceed from left to right, using the largest possible digit in each position.
1080, 9989
smallest=1234 greatest=4321
9542
987,654,321
.961
3,162.27766 is the square root of a smallest 8 digit number and thus the greatest integer having the greatest 7 digit square is 3,162. This is because the square of the next integer i. e. 3,163 is going to be an 8 digit number as discussed above. Thus, 3,162 is the required answer. 3162^2 = 9998244.