Олимпиадный тренинг

Задача 39051. Let's count the numbers - 04


The value of an arithmetic expression
\(2 \cdot 4^{47} + 2 \cdot 4 ^{44}- 2 \cdot 4^{39 } - 2 \cdot 4^{37}-3 \cdot 4^{36}+1\)
written in the number system with base 4. How many significant zeros are in this entry?