  We consider the Hardy-H\'enon parabolic equation $u_t-\Delta u =|x|^a
|u|^{p-1}u$ with $p>1$ and $a\in {\mathbb R}$. We establish the space-time
singularity and decay estimates, and Liouville-type theorems for radial and
nonradial solutions. As applications, we study universal and a priori bound of
global solutions as well as the blow-up estimates for the corresponding initial
boundary value problem.
