According to Yu Hua, a professor of Chinese once ran his book 许三观卖血记 (translated as Chronicle of a Blood Merchant) through the data cruncher, and calculated the number of different characters Yu Hua had used in writing the book. The grand total was 486. Is that even possible?
Update: I asked Yu Hua for more details, he went digging, and it turns out this was quite wrong. The actual numbers are 1,909 characters for Chronicle of a Blood Merchant, and 1,907 characters in To Live. Far more than 486 characters; still far, far less than you'd expect for two of the more influential novels of the past couple decades.