import sys 

read = sys.stdin.buffer.read

readline = sys.stdin.buffer.readline

readlines = sys.stdin.buffer.readlines

N = int(readline())

A = []

while(N>26):

    s = N % 26

    if s == 0:

      A.append(26)

      N = (N-26) // 26

    else:

      A.append(s)

      N = (N-s) // 26

A.append(N)

A = A[::-1]

ans = ''

d = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']

for i in A:

  ans += d[i-1]

print(ans)
import sys 

read = sys.stdin.buffer.read

readline = sys.stdin.buffer.readline

readlines = sys.stdin.buffer.readlines

N = int(readline())

res = ''

while(N):

    N -= 1

    res += chr(ord('a') + N % 26)

    N //= 26

print((res[::-1]))
import sys

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
N = int(readline())
A = []
while N > 26:
    s = N % 26
    if s == 0:
        A.append(26)
        N = (N - 26) // 26
    else:
        A.append(s)
        N = (N - s) // 26
A.append(N)
A = A[::-1]
ans = ""
d = [
    "a",
    "b",
    "c",
    "d",
    "e",
    "f",
    "g",
    "h",
    "i",
    "j",
    "k",
    "l",
    "m",
    "n",
    "o",
    "p",
    "q",
    "r",
    "s",
    "t",
    "u",
    "v",
    "w",
    "x",
    "y",
    "z",
]
for i in A:
    ans += d[i - 1]
print(ans)

import sys

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
N = int(readline())
res = ""
while N:
    N -= 1
    res += chr(ord("a") + N % 26)
    N //= 26
print((res[::-1]))

-A = [] -while N > 26: -    s = N % 26 -    if s == 0: -        A.append(26) -        N = (N - 26) // 26 -    else: -        A.append(s) -        N = (N - s) // 26 -A.append(N) -A = A[::-1] -ans = "" -d = [ -    "a", -    "b", -    "c", -    "d", -    "e", -    "f", -    "g", -    "h", -    "i", -    "j", -    "k", -    "l", -    "m", -    "n", -    "o", -    "p", -    "q", -    "r", -    "s", -    "t", -    "u", -    "v", -    "w", -    "x", -    "y", -    "z", -] -for i in A: -    ans += d[i - 1] -print(ans) +res = "" +while N: +    N -= 1 +    res += chr(ord("a") + N % 26) +    N //= 26 +print((res[::-1]))