1366 - Incorrect integer value: '' for column 'customer_id' at row 1

insert into whos_online (customer_id, full_name, session_id, ip_address, time_entry, time_last_click, last_page_url) values ('', 'Guest', '6t1cjit5l4n154iqvqrbdbpfq3', '216.73.217.80', '1790178280', '1790178280', '/product_info.php?XTCsid=0308d34f52db367f9a7068f51bec2a23&info=p14_65-drinking-cups-1-2-Liter.html')

[XT SQL Error]