Does there exist a positive power of $2$ whose digits in decimal representation can be rearranged to form a power of $3$?
How do we deal with the last digits of powers of $3$? We know that a power of $3$ ends in $1,3,9,7,$ but how do we deal with the other digits?
The answe is no :
If you rearrange the digits of a power of $2$, the digit-sum will not be divisble by $3$, hence the number will not be divisible by $3$. In particular, it will not be a power of $3$.