You ca$$ tell if a binary number is odd or even by

the leftmost $($most significant$)$ bit will be $1$ if even and $0$ if odd

the leftmost $($most significant$)$ bit will be $1$ if odd and $0$ if even

the rightmost bit $($least significant$)$ will be $1$ if even and $0$ if odd

the rightmost bit $($least significant$)$ will be $1$ if odd and $0$ if even