1 GGy (Gigagray) is equal to 99,999,999,999.99998 cGy (Centigray). To convert from Gigagray to Centigray, multiply by 99,999,999,999.99998 or divide by 0.000000000010000000000000001.
Ninety-Nine Billion Nine Hundred Ninety-Nine Million Nine Hundred Ninety-Nine Thousand Nine Hundred Ninety-Nine Point Nine Nine Nine Nine Eight Centigray