Caitanya-caritāmṛta 20.321
caudda eka dine, māse cāri-śata biśa brahmāra vatsare pañca-sahasra calliśa
[chaudda eka dine, maase chaari-shata bisha brahmaara vatsare pancha-sahasra challisha]
Blended reading (Sanskrit + English inline)
caudda eka dine, māse cāri-śata biśa brahmāra vatsare pañca-sahasra calliśa
“There are 14 manvantara-avatāras in one day of Brahmā, 420 in one month, and 5,040 in one year.
My note
Source: vedabase.io