➗ 整除判断（2-13）Divisibility Test Calculator
判断整数能否被 2-13 及自定义除数整除，并说明常用规则。本地处理。可设置「整数」、「自定义除数（可选）」。Check whether an integer is divisible by 2-13 and a custom divisor, with the usual rules. Processed locally. Settings: Integer, Custom divisor (optional).
使用说明与常见问题How-to & FAQ
「整除判断（2-13）」是什么？What is the Divisibility Test Calculator tool?
判断整数能否被 2-13 及自定义除数整除，并说明常用规则。本地处理。可设置「整数」、「自定义除数（可选）」。Check whether an integer is divisible by 2-13 and a custom divisor, with the usual rules. Processed locally. Settings: Integer, Custom divisor (optional).
如何使用「整除判断（2–13）」？How do I use the Divisibility Test Calculator tool?
填写一个整数，可再填一个自定义除数，即可看到它能否被 2–13 及该除数整除，以及对应的判断规则。结果会随输入实时更新。Enter an integer, and optionally a custom divisor, to see whether it is divisible by 2–13 and that divisor, with the rule used for each. The result updates as you type.
规则？Rules?
3 和 9：各位数字和能被整除；4：末两位；8：末三位；11：奇偶位数字和之差。3 and 9: digit sum; 4: last two digits; 8: last three; 11: alternating digit-sum difference.
能举个计算实例吗？Can you show a worked example?
例如在「整除判断（2-13）」中填 整数 = 1260，结果区显示：÷2：✔ 能整除；÷3：✔ 能整除；÷4：✔ 能整除；÷5：✔ 能整除；÷6：✔ 能整除；÷7：✔ 能整除；÷8：✘ 余 4；÷9：✔ 能整除；÷10：✔ 能整除；÷11：✘ 余 6；÷12：✔ 能整除；÷13：✘ 余 12For example, entering Integer = 1260 in the Divisibility Test Calculator gives: ÷2: ✔ divisible; ÷3: ✔ divisible; ÷4: ✔ divisible; ÷5: ✔ divisible; ÷6: ✔ divisible; ÷7: ✔ divisible; ÷8: ✘ remainder 4; ÷9: ✔ divisible; ÷10: ✔ divisible; ÷11: ✘ remainder 6; ÷12: ✔ divisible; ÷13: ✘ remainder 12
哪些输入会被检查？Which inputs are validated?
「整除判断（2-13）」会检查这些输入——「自定义除数（可选）」：可留空；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The Divisibility Test Calculator checks its inputs — "Custom divisor (optional)": optional; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem instead of showing a number.
有哪些选项可以调整？What options can I adjust?
「整除判断（2-13）」的设置：「整数」默认 1260；「自定义除数（可选）」可留空。每次生成结果都按当前设置处理。Settings in the Divisibility Test Calculator — "Integer" default 1260; "Custom divisor (optional)" optional. The result always uses the current settings.
计算精度如何？How precise are the results?
「整除判断（2-13）」使用 JavaScript 双精度浮点数（约 15–16 位有效数字），部分功能使用 BigInt 处理大整数。The Divisibility Test Calculator uses double-precision floating point (about 15–16 significant digits); some features use BigInt for large integers.
「整除判断（2-13）」免费吗？需要注册吗？Is the Divisibility Test Calculator free? Do I need an account?
「整除判断（2-13）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Divisibility Test Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.