Surya Siddhanta
वसुद्व्यष्टाद्रिरूपाङ्कसप्ताद्रितिथयो युगे।(१५७७९१७८२८) चान्द्राः खाष्टखखव्योमखाग्निखर्तुनिशाकराः ॥(१६०३००००८०)
There are 1,577,917,828 terrestrial days and 1,603,000,080 lunar days in a great yuga.
english translation
vasudvyaSTAdrirUpAGkasaptAdritithayo yuge।(1577917828) cAndrAH khASTakhakhavyomakhAgnikhartunizAkarAH ॥(1603000080)
hk transliteration by Sanscript