The number 1 followed by 21 zeros (1,000,000,000,000,000,000,000) is called a Sextillion.
According to the provided reference (Names of Big Numbers), the names of large numbers are as follows:
| Number | Scientific Notation | Name |
|---|---|---|
| 1,000,000,000,000,000,000 | 1018 | Quintillion |
| 1,000,000,000,000,000,000,000 | 1021 | Sextillion |
| 1,000,000,000,000,000,000,000,000 | 1024 | Septillion |
| 1,000,000,000,000,000,000,000,000,000 | 1027 | Octillion |
Therefore, 1,000,000,000,000,000,000,000, represented as 1 x 1021, is indeed a Sextillion.
