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Self-dividing Numbers
A number is self-dividing from the left if each digit is a divisor of the number formed by the digits to its left, e.g.: 513 because 5 is divisible by 1, and 51 is divisible by 3. A number is self-dividing from the right if each digit is a divisor of the number formed by the digits that follow, e.g.: 7210 because 0 is divisible by 1, 10 is divisible by 2, and 210 is divisible by 7.
Challenger
Determine the largest number that is self-dividing from the left, made up of unique digits.
Mastermind
Determine the largest number that is self-dividing from the right, made up of unique digits.