You can see this website http://graphics.stanford.edu/~seander/bithacks.html
Reversing bit sequences
Reverse bits the obvious way
Reverse bits in word by lookup table
Reverse the bits in a byte with 3 operations (64-bit multiply and modulus division)
Reverse the bits in a byte with 4 operations (64-bit multiply, no division)
Reverse the bits in a byte with 7 operations (no 64-bit, only 32)
Reverse an N-bit quantity in parallel with 5 * lg(N) operations
