#include <iostream>
int main(void)
{
unsigned long microseconds = 49198630575;
long milliseconds = (long)(microseconds / 1000) % 1000;
long seconds = (((long)(microseconds / 1000) - milliseconds) / 1000) % 60;
long minutes = (((((long)(microseconds / 1000) - milliseconds) / 1000) - seconds) / 60) % 60;
long hours = ((((((long)(microseconds / 1000) - milliseconds) / 1000) - seconds) / 60) - minutes) / 60;
std::cout << hours << ":" << minutes << ":" << seconds << "." << milliseconds;
}
/*
run:
13:39:58.630
*/