Impossible. With all multiples of nine the product of its digits is 9. Take, for exampe, 117 or 153.
420
No. To find if a number is a factor of 3, add the number's digits. If the resulting number is a multiple of 3, then the original number is a multiple of 3. In 4339, the digits of the number added together is 19, which is not a multiple of 3.
A number is divisible by 3 if the sum of its digits is a multiple of 3. A number is divisible by 6 if the sum of its digits is a multiple of 3 and it's even. A number is divisible by 9 if the sum of its digits is a multiple of 9.
four times the number
If the number is even, it is a multiple of 2 If the sum of the digits make a number divisible by 3, the number is a multiple of 3 If the number ends in 5 or 0, the number is a multiple of 5 If the number is divisible by 2 and 3, the number is a multiple of 6 If the sum of the digits make a number divisible by 9, the number is a multiple of 9
21 or 35
The number is 35.
144
Sixteen Digits
52 is a number whose digits have a product of 10.
420
88
No. To find if a number is a factor of 3, add the number's digits. If the resulting number is a multiple of 3, then the original number is a multiple of 3. In 4339, the digits of the number added together is 19, which is not a multiple of 3.
300, 600 and 900.
A number is divisible by 3 if the sum of its digits is a multiple of 3. A number is divisible by 6 if the sum of its digits is a multiple of 3 and it's even. A number is divisible by 9 if the sum of its digits is a multiple of 9.
four times the number
If the sum of the digits of a number is a multiple of 9, the number is a multiple of 9.