def dec_converter(val, base = 10):
digits = '0123456789ABCDEFGH'
dig = list(digits)
if base > len(digits):
raise ValueError("база дуже велика")
out = ""
res = val
while res > 0:
res , zal = divmod(res,base)
out+= digits[zal]
return out[::-1]
print(dec_converter(2739857903258 , 16))
ZGVmIGRlY19jb252ZXJ0ZXIodmFsLCBiYXNlID0gMTApOgogICAgZGlnaXRzID0gJzAxMjM0NTY3ODlBQkNERUZHSCcKICAgIGRpZyA9IGxpc3QoZGlnaXRzKQogICAgaWYgYmFzZSA+IGxlbihkaWdpdHMpOgogICAgICAgIHJhaXNlIFZhbHVlRXJyb3IoItCx0LDQt9CwINC00YPQttC1INCy0LXQu9C40LrQsCIpCiAgICBvdXQgPSAiIgogICAgcmVzID0gdmFsCiAgICB3aGlsZSByZXMgPiAwOgogICAgICAgIHJlcyAsIHphbCA9IGRpdm1vZChyZXMsYmFzZSkKICAgICAgICBvdXQrPSBkaWdpdHNbemFsXQogICAgcmV0dXJuIG91dFs6Oi0xXQpwcmludChkZWNfY29udmVydGVyKDI3Mzk4NTc5MDMyNTggLCAxNikp