Which bank has highest number of branches in the world? 

SBI, which is India's large Bank merged five of its Associate Banks (State Bank of Bikaner & Jaipur, State Bank of Hyderabad, State Bank of Mysore, State Bank of Patiala and State Bank of Travancore) and Bharatiya Mahila Bank with itself. This is the first ever large scale consolidation in the Indian Banking Industry. With the merger, State Bank of India will enter the league of top 50 global banks with a balance sheet size of ₹41 trillion, 277,000 employees, 500 million customers, and more than 22,500 branches and 58,000 ATMs