#include <bits/stdc++.h>
using namespace std;
const double eps(1e-8);
const double pi(3.14159265358979);
const int K = 33, mod = 1000000007;
struct matrix {
  long long a[K][K];
} t[K] = {}, ans = {{}}, pre[K] = {}, suf[K] = {};
long long n;
int k;
inline void multi(const matrix &m1, const matrix &m2, matrix &to) {
  static matrix tmp = {{}};
  for (int i = 0; i <= k; ++i)
    for (int j = 0; j <= k; ++j) {
      tmp.a[i][j] = 0;
      for (int p = 0; p <= k; ++p)
        (tmp.a[i][j] += m1.a[i][p] * m2.a[p][j]) %= mod;
    }
  to = tmp;
}
void init() {
  cin >> n >> k;
  for (int i = 0; i <= k; ++i)
    for (int j = 0; j <= k; ++j) ans.a[i][j] = i == j;
  for (int p = 0; p < k; ++p)
    for (int i = 0; i <= k; ++i)
      for (int j = 0; j <= k; ++j) t[p].a[i][j] = i == j || i == p;
}
void work() {
  vector<int> bit;
  for (; n; n /= k) bit.push_back(n % k);
  bit.push_back(0);
  partial_sum(bit.rbegin(), bit.rend(), bit.rbegin());
  for (auto p = 0u; p < bit.size() - 1; ++p) {
    for (int i = bit[p] - 1; i >= bit[p + 1]; --i) multi(t[i % k], ans, ans);
    pre[0] = t[0];
    for (int i = 1; i < k; ++i) multi(pre[i - 1], t[i], pre[i]);
    suf[k - 1] = t[k - 1];
    for (int i = k - 2; i >= 0; --i) multi(t[i], suf[i + 1], suf[i]);
    t[0] = suf[0];
    for (int i = 1; i < k; ++i) multi(suf[i], pre[i - 1], t[i]);
  }
  long long sum = 0;
  for (int i = 0; i <= k; ++i) sum += ans.a[i][k];
  cout << sum % mod << endl;
}
int main() {
  init();
  work();
  return 0;
}
