ndivtri

#include <iostream>
using namespace std;

short NrDiv(int x) /// Calculez numarul nrd de divizori ai lui x
{
    short nrd=1,p=0;
    int k=x;
    while(!(k&1))
        ++p,k>>=1;
    nrd*=p+1;
    for(int d=3;d*d<=k;d+=2)
    {
        p=0;
        while(k%d==0)
            ++p,k/=d;
        nrd*=p+1;
    }
    if(k>1)
        nrd*=2;
    return nrd;
}

int main()
{
	short n;
	cin>>n;
	short nrd=0;
	int tri=0,i=1;
	while(nrd<=n)
        tri+=i,nrd=NrDiv(tri),++i;
	cout<<tri;
	return 0;
}