能被2整除的数就是偶数。其数学表达式为2n-2(n≠0),偶数又叫做双数。小学数学教材是在自然数范围内来研究数的整除的,不包括0,也不提0是任何数的倍数,所以也就不提0是偶数。但不能因此而说0不是偶数。偶数的运算有下列性质:任意多个偶数的和(或差、积)是偶数。不能被2整除的数就是奇数。其数学表达式为2 n-1(n≠0),奇数又叫做单数。 The number that can be divisible by 2 is even. Its mathematical expression is 2n-2 (n ≠ 0), even number is also called a double number. Primary mathematics textbooks are in the range of natural numbers to study the number of divisions, excluding 0, do not mention 0 is a multiple of any number, so do not mention 0 is even. But it can not be said that 0 is not even. The operations of even numbers have the following properties: The sum (or difference, product) of any number of even numbers is even. The number that can not be divisible by 2 is odd. Its mathematical expression is 2 n-1 (n ≠ 0), odd number is also called singular.