CC MADHYA 20.322
śateka vatsara haya jīvana' brahmāra
pañca-lakṣa cāri-sahasra manvantarāvatāra
SYNONYMS

śateka vatsara haya—there are one hundred years; jīvana—the duration of life; brahmāra—of Brahmā; pañca-lakṣa—500,000; cāri-sahasra—4,000; manu-antara-avatāra—incarnations of Manu.

TRANSLATION

"During the hundred years of Brahmā's life, there are 504,000 manvantara-avatarās.