The system of Japanese numerals are just the same as those of the Chinese numerals since both uses Chinese characters. The only notable difference is the Japanese pronunciation. Also, instead of using Chinese characters, they often opt to just use the Arabic system. The numerals are based on decimal (base-10) and are grouped in ten thousands (compare to our grouping of thousands). * 二十 (ni juu) = 2 * 10 = 20 * 三十 (san juu) = 3 * 10 = 30 * 二十一 (ni juu ichi) = (2 * 10) "twenty" + 1 = 21 * 六十五 (roku juu go) = (6 * 10) "sixty" + 5 = 65 See Wikipedia:Japanese numerals for more info.