1113, 1131, 1311, 3111, 1122,1212, 1221, 2112, 2121, 2211
1113 ، 3111 1122 ، 2211 1131 ، 1311 1212 ، 2121 1221 2112
A 9-digit number has a property that the first 'n' digits are divisible by 'n'. There is no '0' in the number and all the digits in the number are distinct. What is the number?
Arrange all the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 to give four different square numbers. (You make a square number when you multiply something by itself, so 49 is square because it is 7 times 7)
It can be easily calculated that the digits 0 to 9 can be arranged into 3628800 distinct ten-digit numbers.
But I also know how many of these numbers are prime.
Do you?
