psql -c command parse "select $$hello$$" failed

Hi.
not sure this is the expected result.

/home/jian/postgres/pg16_test/bin/psql -d test_dev -p 5455 -c "select $$hello$$"
2023-07-04 20:15:51.066 CST [1562050] ERROR:  trailing junk after
numeric literal at or near "884070h" at character 8
2023-07-04 20:15:51.066 CST [1562050] STATEMENT:  select 884070hello884070
ERROR:  trailing junk after numeric literal at or near "884070h"
LINE 1: select 884070hello884070
               ^