The capital letters 1 to 10 are written as: one, two, three, four, five, six, seven, eight, nine, and ten.
Uppercase numbers are a unique Chinese way of writing numbers. Chinese characters with the same pronunciation as the numbers are used to replace the numbers to prevent the numbers from being altered.
According to research, capital numbers were first invented by Wu Zetian and later improved by Zhu Yuanzhang.
Historical origin: The use of uppercase numbers began in the Ming Dynasty. Zhu Yuanzhang issued a decree because of the "Guo Huan Case", a major corruption case at that time, which clearly required that the numbers for accounting must be composed of "one, two, three, four, five, six, seven, eight, nine, ten, one hundred, "Thousand" was changed to "one, two, three, four, five, Lu, seven, eight, nine, ten, hundred (mo), thousand (qian)" and other complex Chinese characters to increase the difficulty of altering the account books. Later, "Mo" and "阡" were rewritten as "百、千" and are still used today.