Since [x] stands for greatest integer function, let us assume, [x]=x, that is x is an integer.
Then
[x]+[2x]+[4x]+[8x]+[16x]+[32x]=12345
x+2x+4x+8x+16x+32x=12345
x(26−12−1)=12345
63x=12345
21x=4115
x=411521 is not an integer.
This contradicts our initial assumption.
Hence not solution is possible.