In this paper, we propose a method for increasing the capacity of Machine-To-Machine (M2M) communication in mobile core networks. The proposed method combines two approaches: bearer aggregation inside mobile core networks for decreasing the load of Evolved Packet Core (EPC) nodes, and applying a Software Defined Networking (SDN) architecture to separate the control and data planes and aggregate control plane nodes in a cloud network environment for resource sharing. The combination of these two approaches is meaningful because they have a complementary relationship. We give a mathematical analysis and numerical results of a performance evaluation of the proposed method. The evaluation results show that we can increase the capacity of a mobile core network for M2M communication by around 30% when one of the two approaches is applied, while the performance gain increases up to 124% when both approaches are combined.