In Jain time‑measurement:

• 1 pūrvāṅga = 84,00,000 (84 lakh) years
• 1 pūrva = 84,00,000 × 84,00,000 years

So,

> 1 purva = 7,05,60,00,00,00,000 years > i.e. 70,56,00,00,00,000 years (about 70.56 trillion years).

So 1 purva is an extremely large unit of time in Jain cosmology.

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