In this research, the electronic and chemical properties of a series of   (  C₅N_)n nanoribbons have been investigated. The effect of nanoribbon length on the polarizability and hyperpolarizability of the molecules has been considered. It has been demonstrated that odd or even number of constructive units impresses on the polarizability of this type of nanoribbons. Clearly,   (  C₅N_)2n nanoribbons show better NLO properties. To survey the chemical properties of considered nanoribbons, the frontier molecular orbitals have been studied. Aromaticity of involving rings in considered nanoribbons has been investigated, too.