#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
struct matrix {
  long long a[35][35];
} a[35], b[35], c, d[35];
long long n;
int K;
inline matrix multi(const matrix &a, const matrix &b) {
  matrix c;
  memset(c.a, 0, sizeof(c.a));
  for (int i = 0; i <= K; i++)
    for (int j = 0; j <= K; j++)
      for (int k = 0; k <= K; k++) (c.a[i][j] += a.a[i][k] * b.a[k][j]) %= MOD;
  return c;
}
inline void merge() {
  b[0] = a[0];
  for (int i = 1; i < K; i++) b[i] = multi(b[i - 1], a[i]);
  d[K - 1] = a[K - 1];
  for (int i = K - 2; i >= 0; i--) d[i] = multi(a[i], d[i + 1]);
  for (int i = 0; i < K; i++) a[i] = i ? multi(d[i], b[i - 1]) : d[i];
}
int main() {
  scanf("%I64d%d", &n, &K);
  for (int i = 0; i < K; i++) {
    for (int j = 0; j < K; j++)
      if (i != j)
        a[i].a[j][j] = 1;
      else
        for (int k = 0; k <= K; k++) a[i].a[k][j] = 1;
    a[i].a[K][K] = 1;
  }
  for (int i = 0; i <= K; i++) c.a[i][i] = 1;
  for (; n; n /= K) {
    int A = n % K;
    if (A) {
      int s = 0, ed;
      long long v;
      for (v = n; v; v /= K) s = (v / K + s) % K;
      ed = (s + A - 1) % K;
      for (;;) {
        c = multi(a[ed], c);
        if (ed == s) break;
        if (--ed < 0) ed += K;
      }
    }
    merge();
  }
  long long res = 1;
  for (int i = 0; i < K; i++) (res += c.a[K][i]) %= MOD;
  printf("%I64d\n", res);
  return 0;
}
