get the_content with ID

gistfile1.txt

// Setting the Post ID in a variable for which the content is required
$the_postid = 20; 

$the_post_content = get_post($the_postid);
$content = $the_post_content->post_content;
$content = apply_filters('the_content', $content);
$content = str_replace(']]>', ']]>', $content);

// Print Content data or further use it as required
echo $content;