Each element in the image of $d_n$ corresponds to an element of order $p^n$ in the homology with integer coefficients. So it suffices to compute the image of $d_1=\beta$ on $H_*(X;Z/p)$$H_*(X;\mathbb{Z}/p)$ to determine the number of summands isomorphic to $Z/p$ in $_*(X;Z)$$H_*(X;\mathbb{Z})$.