Multiple if is_category

Ive an existing code but is too long as ive many categories (>30). If i were to use the below code, it seems too much. Is there a better way to do it?

<?php if ( is_category('1') || is_category('2') || is_category('3') ) {
    echo 'hi';
}
?>

Basically i want all child categories within the main category, not the posts under the child categories. Thanks for your time.