Centummillion or uncentillion is a 1 followed by 306 zeros.
uncentillion.
Duocentillion
In the standard naming system for large numbers, a centillion is equal to 10^303. Therefore, the prefix "un-" would indicate a number that is one less than a centillion, which would be 10^303 - 1. However, this naming system is not universally agreed upon, and different systems may have different names for extremely large numbers. In some systems, "uncentillion" may indeed be considered a number, although it is not commonly used in mainstream mathematics.
how many zeros in one billion
Seven zeros.
33 zeros
there are 21 zeros
12 zeros.12 zeros.12 zeros.12 zeros.
Six zeros: 127,000,000
how many zeros in 12 lakh
10 zeros
101 zeros.