|Is the router configured to respond to pings? Often they are not. Presumably you are trying to ping it by dotted quad rather than name; in that case it shouldn't matter whether it is the default gateway or just another device on the network.|
Assuming that both devices are on the same network, and your netmask settings are correct, they should be able to talk to each other. You don't say whether you can reach the Internet - presumably not, or else what is the problem.
Without knowing the network settings on the devices it's difficult to give a more meaningful answer.