TypeError：无法混合 BigInt 和其他类型，使用显式转换

我正在尝试生成一个 20 位随机数：

let code = Math.floor(10000000000000000000n + Math.random() * 90000000000000000000n)

我尝试过将数字输入BigInt()以及添加一个n之后但仍然出现此错误。

Uncaught TypeError: Cannot mix BigInt and other types, use explicit conversions

// An operation with a fractional result will be truncated when used with a BigInt.

const rounded = 5n / 2n
// ↪ 2n, not 2.5n

// BigInt value can only operator with same type

// random BigInt
BigInt(Math.floor(Math.random() * 10))

// generate a 20 digit random number
BigInt(Math.floor(Math.random() * 100000000000000000000))

你可以检查this https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt