Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
quingentĭes (-tĭens), adv. [quingenti], five hundred times: quingentiens mille, Vitr. 1, 6.
Of money: quingentiens HS., fifty millions of sesterces, Cic. Verr. 2, 2, 38, § 93: miliens et quingentiens, Suet. Aug. 101; id. Galb. 5.