Arduino Mega - 54 or 64 digital pins

Other Hardware 3rd Party Boards
4

so apart of pin 0 and 1 that reserve for communication with computer, can I use all the remain 67 Pins as digital outputs? if I declare them to be an output as the follow:

void setup(){
for (int i = 2; i < 69; i++)
{
pinMode(i, OUTPUT);
}