maximum limit of unsigned long long

guys,a little help here,when i assign a value to the unsigned long long ,the compiler shows ,integer constant is too large for long type..but the strange thing is if i enter the same value using cin,then it is working fine ..can anybody tell me what to do here..i want to store the values beforehand..

#include<cstdio>
#include<iostream>
using namespace std;
int main()
{
unsigned long long int a;
a=916312070471295267;
//cin>>a;
cout<<a;
return 0;
}