Question
Does there exist a perfect square whose digits sum to `2001`?
Justify or provide an example!
Difficulty level (1 very easy - 10 very hard): 3
Topics:
Number Theory
->
Modular Arithmetic / Remainder Arithmetic
->
Divisibility Rules
->
Divisibility Rules by 3 and 9
Number Theory
->
Division
->
Parity (Even/Odd)
Number Theory
->
Prime Numbers
->
Prime Factorization
Proof and Example
->
Proof by Contradiction
注讚讬 讚诪专讬 - 5 years ago