#include <bits/stdc++.h>
#include <algorithm>
using namespace std;


int main() {
    int K;
    int64_t ans = 0;
    cin >> K;
    for(int a = 1; a*a*a <= K; a++) {
        for(int b = a; a*b*b<=K; b++) {
            int cmax = K/(a*b);
            if(a==b) {
                ans += 1+(cmax-b)*3;
            }
            else{
                ans += 3+(cmax-b)*6;
            }
        }
    }
    cout << ans << endl;
}
#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
#include <set>
#include <queue>
#include <cmath>

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<long long> vll;
typedef vector<vector<long long>> vvll;
typedef pair<int,int> pii;
typedef pair<long long, int> pli;
typedef pair<int, long long> pil;

#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define rrep(i, n) for(int i = (int)(n)-1;i >= 0;i--)
#define repr(i, a, b) for(int i = (int)a; i <= (int)b; i++)
#define all(x) (x).begin(),(x).end()
#define sz(x) (x).size()

constexpr ll mod = 998244353;

ll gcd(ll a, ll b){
    if (a%b == 0)return(b);
    else return(gcd(b, a%b));
}

ll inv(ll x){
    ll res = 1;
    ll k = mod - 2;
    ll y = x;
    while(k){
        if(k&1)res = (res*y)%mod;
        y = (y*y) % mod;
        k /= 2;
    }
    return res;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    ll k;
    cin >> k;

    ll ret = 0;

    repr(i,1,k) {
        ll bc = k/i;
        repr(j,1,bc) {
            ret += bc/j;
        }
    }

    cout << ret << endl;
}
