error: Ambiguous call to overloaded function

[Faramar]

So I write this program

#include <iostream>
#include <cmath>
using namespace std;
int main() 
{
	int n; 
	int i=2; 
	int prime = true; 
	cout << "Pick a number: ";
	cin >> n;
	while (i <= sqrt(n)) 
	{ 
		if (n % i == 0) 
			prime = false; 
		i++; 
	}
	if (prime)
	cout << "Number is prime." << endl;
	else
	cout << "Number is not prime." << endl;
	system("PAUSE");
	return 0;
}

And i get this error: error C2668: 'sqrt' : ambiguous call to overloaded function

I don't know if it's because of any mistake I made (I can't find one), or what it is. I'd appreciate your help.

[hamsterman]

There is no sqrt overloaded for an integer argument there are only for float, double and long double.
You could make it i <= sqrt(float(n)).

Note though that instead of i <= sqrt(n) you could have i*i <= n.