21的倍数:21,42,63,84,105,126,147,168,189/21的因数:1,3,7,2122的倍数:22,44,66,88,110,132,154,176,198/22的因数:1,2,11,2223的倍数:23,46,69,92,115,138,161,184,207/23的因数:1,2324的倍数:24,48,72,96,120,144,168,192,216/24的因数:1,2,3,4,6,8,12,2425的倍数:25,50...
是8 只要是8的倍数,那这个数含的因数都有1,2,4,8两个正整数相乘,那么这两个数都叫做积的因数,或称为约数。