Check If post id exist in custom post type , outside of loop

You can use:

echo 'movie' === get_post_type( 123 ) ? 'Yes' : 'No'; 

But if you need to check it many times in your theme, you might consider defining your own helper function:

if( ! function_exists( 'is_movie' ) )
{
    function is_movie( $mixed = null )
    {
        return 'movie' === get_post_type( $mixed );
    }
}

It might return true when $mixed is empty, \WP_Post object or a post ID.

So if you want to know if there exists a movie with ID 123:

echo is_movie( 123 ) ? 'Yes' : 'No';

or just is_move() within the loop, to check the current post ID.

If you only need to check if the ID 123 exists, then just use get_post().

For example:

echo is_null( get_post( 123 ) ) ? 'No' : 'Yes';

error code: 523