My code

… was written in C++11 and can be compiled with G++, Clang++, Visual C++. You can download it, too. Or just jump to my GitHub repository.

       
#include <string>
       
#include <iostream>
       
#include <algorithm>
       
 
       
// convert a string to a number

       
unsigned long long str2num(const std::string& x)
       
{
       
  // process string from left to right
       
  unsigned long long result = 0;
       
  for (auto c : x)
       
  {
       
      // shift digits
       
      result *= 10;
       
      // add new digit on the right-hand side
       
      result += c - '0'; // was ASCII
       
  }
       
  return result;
       
}
       
 
       
int main()
       
{
       
  // available digits
       
  std::string pan = "0123456789"; // unlike other problems, zero is allowed this time
       
 
       
  // remove a few digits if test case requires this
       
  unsigned int maxDigit;
       
  std::cin >> maxDigit;
       
  pan.erase(maxDigit + 1);
       
 
       
  // all divisors
       
  const unsigned int primes[] = { 2,3,5,7,11,13,17 };
       
 
       
  // result
       
  unsigned long long sum = 0;
       
 
       
  // look at all permutations
       
  do
       
  {
       
    // let's assume it's a great number ;-)
       
    bool ok = true;
       
 
       
    // check each 3-digit substring for divisibility
       
    for (unsigned int i = 0; i + 2 < maxDigit; i++)
       
    {
       
      // check pan[1..3] against primes[0],
       
      // check pan[2..4] against primes[1],
       
      // check pan[3..5] against primes[2] ...
       
      std::string check = pan.substr(i + 1, 3);
       
      if (str2num(check) % primes[i] != 0)
       
      {
       
        // nope ...
       
        ok = false;
       
        break;
       
      }
       
    }
       
 
       
    // passed all tests, it's great indeed !
       
    if (ok)
       
      sum += str2num(pan);
       
  } while (std::next_permutation(pan.begin(), pan.end()));
       
 
       
  std::cout << sum << std::endl;
       
  return 0;
       
}

This solution contains 9 empty lines, 16 comments and 3 preprocessor commands.