twenty billion nine hundred ninety nine million nine hundred ninety nine thousand nine hundred sixty six Pronunciation in english(IPA) :
ˈtwɛnti ˈbɪljən nʌɪn ˈhʌndrəd ˈnʌɪnti nʌɪn ˈmɪljən nʌɪn ˈhʌndrəd ˈnʌɪnti nʌɪn ˈθaʊz(ə)nd nʌɪn ˈhʌndrəd ˈsɪksti sɪks