You must use each of the integers from 0 to 5 exactly once to fill in the blanks in the multiplication problem below.

_ _ _ x _ _ x _ = 

What is the largest possible value you can create?

All my digits are non-zero perfect squares. If you treat my first two digits as a two-digit number, and treat my last two digits as a two-digit number, the sum of these two numbers is also a perfect square. If I am a three digit number, what numbers could I be?

I'm a three digit number. Reverse my digits and subtract, and the result is 198. Reverse my digits and add, and the result is 1272.

What number am I?

I am a three digit number, and the following things are true about me:

1. The product of two of my digits is 8.
2. The sum of my digits is 13.
3. My first digit is four times my second digit.

What number am I?

Happy New Year! I am a four-digit year, and my last two digits are a perfect square. The sum of my first and third digits is a perfect square. My second digit is a perfect square. All my digits add to a perfect square.

If you subtract my first, second, and third digit from my last digit, you get a perfect square.

If you subtract my third digit from my first digit, you get a perfect square.

Oh, by the way, I'm a perfect square.

What year am I?

In the addition problem below, some digits are missing. They have been replaced by x and y. Find the values of x and y.

3xy2 + 3y1 = 40x3

Find the sum of all the integers between one and 100 which have 14 as the sum of their digits.

I'm a three digit number. My first two digits multiply to 12, and my last two digits add to 14. What number am I?