No. The blue whale has the biggest brain in terms of volume. However, the size of a brain is not a good measure of intelligence any more than the ability to speak.
Your brain is more complex than animals (you are a type of monkey ya'know) so one thing we can do that animals can't is think more, we also have more motor functions, therefore more coordination when...
The sperm whale is supposed to have the largest brain in the world, as far as mass and size of the brain alone, not in proportion to its body size. Speaking in terms of mass and in proportion to body...