For example 47 is not a Lychrel Number as 47 + 74 = 121

Lychrel numbers: Are those numbers that cannot form a palindrome when repeatedly reversed and added to itself.

Perfect numbers or Amicable numbers: Perfect numbers are those numbers which are equal to the sum of their proper divisors.

Goldbech`s conjecture: Every even integer greater than 2 can be expressed as the sum of 2 primes.

If we have to subtract a constant K such that the product gets its minimum value, then subtract it from the smallest value where smallest value-k should be greater than 0

For a product of N numbers, if we have to subtract a constant K such that the product gets its maximum value, then subtract it from a largest value such that largest value-k is greater than 0.

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Basic number theory concepts