Magento 2 - How to CAST & CONVERT Datatype VARCHAR to INT in query?

Question

I have custom extension in magento 2. In that, saleslist table to save order & product list with seller.

saleslist table

mageproduct_id | order_id | seller_id | magequntity(varchar)

select * from saleslist where order_id in (36,37) and mageproduct_id = 2 and seller_id = 20 order by magequantity desc

I am applying above query from below code & this successful return data but not able to sort by magequantity. It's obvious because of VARCHAR datatype.

$trackingcol_saleslist = $this->_objectManager->create('<extesion>\<module>\Model\Saleslist')
                                                    ->getCollection()
                                                    ->addFieldToFilter(
                                                        'mageproduct_id',
                                                        $product_id
                                                    )->addFieldToFilter(
                                                        'order_id',
                                                        ['in' => $order_id_list]
                                                    )->addFieldToFilter(
                                                        'seller_id',
                                                        $sellerId
                                                    )->setOrder('magequantity','DESC');

                                                foreach ($trackingcol_saleslist as $info) {
                                                 print_r($info->getData());
                                                }

I have other option to achieve this like, changing column datatype VARCHAR to INT or taking $trackingcol_saleslist as array & apply array sorting.

But I am looking for applying CAST & CONVERT Datatype VARCHAR to INT in magento query. Is this possible in magento?