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In this paper, the finite-size Dicke model of arbitrary number of qubits is solved analytically in a unified way within extended coherent states. For the $N=2k$ or $2k-1$ Dicke models ( k is an integer), the G -function, which is only an energy dependent $k\times k$ determinant, is derived in a transparent manner. The regular spectrum is completely and uniquely given by stable zeros of the G -function. The closed-form exceptional eigenvalues are also derived. The level distribution controlled by the pole structure of the G -functions suggests non-integrability for $N\gt 1$ model at any finite coupling in the sense of recent criteria found in the literature. A preliminary application to the exact dynamics of genuine multipartite entanglement in the finite- N Dicke model is presented using the obtained exact solutions.