Is this possible 1

A positive integer with $n$ number of digits is called special ( $\overline{a_1a_2a_3a_4\dots a_{n}}$ ), if $\overline{a_1a_2a_3a_4\dots a_{n}}+\overline{a_{n}a_{n-1}a_{n-2}\dots a_3a_2a_1}$ has only odd digits. ( $a_{n}\neq0$ .)

Which of the following could be the number of a special number's digits?