def get_ordinal_indicator(number):
    """Get the ordinal indicator suffix applicable to the supplied number.

     Ordinal numbers are words representing position or rank in a sequential
     order (1st, 2nd, 3rd, etc).
     Ordinal indicators are the suffix characters (st, nd, rd, th) that, when
     applied to a numeral (int), denote that it an ordinal number.

    :param number: int
    :type: int
    :return: ordinal indicator appropriate to the number supplied.
    :rtype: str
    """
    str_num = str(number)
    digits = len(str_num)
    if str_num[-1] == '1' and not (digits >= 2 and str_num[-2:] == '11'):
        return 'st'
    elif str_num[-1] == '2' and not (digits >= 2 and str_num[-2:] == '12'):
        return 'nd'
    elif str_num[-1] == '3' and not (digits >= 2 and str_num[-2:] == '13'):
        return 'rd'
    else:
        return 'th'
