Hi,
hikashop_get is a function to initiliaze class instances, not to load elements information. So that code cannot possibly work. You would first have to get the current product id, then load the product class, then load the product data using the product class and then you can echo the product name.
Supposing that you're on the product page, you can use such code to do that:
$product_id = (int)hikashop_getCID('product_id');
$class = hikashop_get('class.product');
$product = $class->get($product_id);
echo $product->product_name;