import java.lang.*;  
import java.io.*;  
import java.util.*;  
  
class Main {
// Driver code
 public static String getAlpha(long num) {

    String result = "";
    while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    }

    return result;
  } 
public static void main (String[] args) 
{ 
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    System.out.println(getAlpha(n));
} 
}  import java.lang.*; lang.* java import java.io.*; io.* java import java.util.*; util.* java class Main {
// Driver code
 public static String getAlpha(long num) {

    String result = "";
    while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    }

    return result;
  } 
public static void main (String[] args) 
{ 
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    System.out.println(getAlpha(n));
} 
} Main // Driver code
 public static String getAlpha(long num) {

    String result = "";
    while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    }

    return result;
  } getAlpha {

    String result = "";
    while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    }

    return result;
  } String result = ""; result "" while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    } num > 0 num 0 {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    } num-- num long remainder = num % 26; remainder num % 26 num 26 char digit = (char) (remainder + 97); digit (char) (remainder + 97) remainder 97 result = digit + result result digit + result digit result num = (num - remainder) / 26 num (num - remainder) / 26 (num - remainder) num remainder 26 return result; result long num num public static void main (String[] args) 
{ 
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    System.out.println(getAlpha(n));
} main { 
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    System.out.println(getAlpha(n));
} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long n = sc.nextLong(); n sc.nextLong() sc.nextLong sc System.out.println(getAlpha(n)) System.out.println System.out System System.out getAlpha(n) getAlpha n String[] args args
import java.lang.*;  
import java.io.*;  
import java.util.*;  
  
class Main {
// Driver code
 public static String getAlpha(long num) {

    String result = "";
    while (num > 0) {
      num--; // 1 => a, not 0 => a
      long remainder = num % 26;
      char digit = (char) (remainder + 97);
      result = digit + result;
      num = (num - remainder) / 26;
    }

    return result;
  } 
public static void main (String[] args) 
{ 
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    System.out.println(getAlpha(n));
} 
} 