# your code goes here
import string
import math

DIGITS = string.ascii_letters
def to26base(num: int) -> str:
	ret = ""
	while num:
		ret += DIGITS[num%26]
		num //= 26
	return ret[::-1] or DIGITS[0]

def format_big_num(num: int) -> str:
	exp = int(math.log10(num))
	adjusted_exp = exp // 3 - 1
	if adjusted_exp < 0:
		return str(num)
	base26exp = to26base(adjusted_exp)
	rem = num // 10**((adjusted_exp + 1) * 3)
	return str(rem) + base26exp
	
for x in [1, 10, 100, 1000, 2000, 5000, 100000, 2**64, 2**128, 2**256, 2**1024]:
	print(format_big_num(x))