#include <bits/stdc++.h>
using namespace std;
const int MAX = 700000;
const int MOD = 1000000007;
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}
long long COM(int n, int k) {
  if (n < k) return 0;
  if (n < 0 || k < 0) return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
long long int maxtime(long long int x, long long int y) {
  return (x + y - 1) / y;
}
long long int lcm(long long int number1, long long int number2) {
  long long int m = number1;
  long long int n = number2;
  if (number2 > number1) {
    m = number2;
    n = number1;
  }
  long long int s = -1;
  while (s != 0) {
    s = m % n;
    m = n;
    n = s;
  }
  return m;
}
long long int gcd(long long int number1, long long int number2) {
  long long int m = number1;
  long long int n = number2;
  return m / lcm(m, n) * n;
}
int main() {
  long long int ans;
  cin >> ans;
  string oo = to_string(ans);
  reverse(oo.begin(), oo.end());
  long long int sum = 0;
  int a, b, c;
  a = 0;
  b = 0;
  c = 0;
  if (ans < 357) {
    cout << 0;
    return 0;
  }
  long long int keta = 0;
  long long int s = ans;
  while (s > 0) {
    s = s / 10;
    keta++;
  }
  for (int i = keta; i > 1; i--) {
    if (i == 2) {
      long long int p = ans / 100;
      for (int j = p * 100; j <= ans; j++) {
        int a1 = 0;
        int b1 = 0;
        int c1 = 0;
        int d1 = 0;
        long long int f = j;
        while (f > 0) {
          int d = f % 10;
          f = f / 10;
          if (d == 3) {
            a1 = a1 + 1;
          } else if (d == 5) {
            b1 = b1 + 1;
          } else if (d == 7) {
            c1 = c1 + 1;
          } else {
            d1 = d1 + 1;
          }
        }
        if (d1 > 0) {
          continue;
        }
        if ((a1 > 0) && (b1 > 0) && (c1 > 0)) {
          sum = sum + 1;
        }
      }
      break;
    }
    if ((oo[i - 1] - '0') > 7) {
      int n = 0;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i) - 3 * pow(2, i) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i) - 2 * pow(2, i) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i) - pow(2, i);
      } else if (n == 3) {
        sum = sum + pow(3, i);
      }
      break;
    }
    if ((oo[i - 1] - '0') == 7) {
      int n = 0;
      a = a + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      a = a - 1;
      n = 0;
      b = b + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      c = c + 1;
      continue;
    }
    if ((oo[i - 1] - '0') == 6) {
      int n = 0;
      a = a + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      a = a - 1;
      n = 0;
      b = b + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      break;
    }
    if ((oo[i - 1] - '0') == 5) {
      int n = 0;
      a = a + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      a = a - 1;
      b = b + 1;
      continue;
    }
    if ((oo[i - 1] - '0') == 4) {
      int n = 0;
      a = a + 1;
      if (a != 0) {
        n = n + 1;
      }
      if (b != 0) {
        n = n + 1;
      }
      if (c != 0) {
        n = n + 1;
      }
      if (n == 0) {
        sum = sum + pow(3, i - 1) - 3 * pow(2, i - 1) + 3;
      } else if (n == 1) {
        sum = sum + pow(3, i - 1) - 2 * pow(2, i - 1) + 1;
      } else if (n == 2) {
        sum = sum + pow(3, i - 1) - pow(2, i - 1);
      } else if (n == 3) {
        sum = sum + pow(3, i - 1);
      }
      break;
    }
    if ((oo[i - 1] - '0') == 3) {
      a = a + 1;
      continue;
    }
    if ((oo[i - 1] - '0') < 3) {
      break;
    }
  }
  for (int i = keta - 1; i > 2; i--) {
    sum = sum + pow(3, i) - 3 * pow(2, i) + 3;
  }
  cout << sum;
}
