This chapter demonstrates the impact of efficient quantum arithmetic circuits on two important application domains: quantum machine learning (QML) and quantum cryptanalysis. Firstly, we discuss how to map our design onto real quantum hardware architectures, specifically focusing on the verification of our design using NISQ devices, which are currently the only available hardware architecture in quantum computing. Afterward, each application highlights the potential of quantum arithmetic to enhance overall computational efficiency across diverse domains. The following sections provide the details of our research.