Now-a-days most software projects have more candidate requirements. So it is vital for software companies to use different prioritization techniques to select valuable requirements among the candidate requirements. But software companies usually face a lot of challenges in using AHP such as increase in time and complexity with respect to number of comparisons. In this paper, we present previous work carried out in this research area and industrial study to identify the challenges software companies face while prioritizing large number of requirements using AHP. Different types of prioritization techniques have been developed to resolve these challenges. This paper focus on Numeral assignment technique which groups requirements into three categories: critical, standard and optional and AHP which prioritize requirements based on pair-wise comparisons. In this article we proposed a model i.e., NAcAHP where in which pair-wise comparison of AHP is applied on critical group of Numeral assignment technique for prioritizing the requirements. The result shows that the proposed model minimizes the time and complexity of pair wise comparison.