C++ 我可以将unsigned long long变量视为分配另一个变量的地址吗

我感兴趣的是，unsigned long long变量是否可以被视为地址，结果似乎是正确的？

int var = 0;
// the variable var's address is 0x7fffffffe4a4 now in my system
unsigned long long ull = 0x7fffffffe4a4;
scanf("%d", ull);  // I try to use ull as var's address and assign a value to var
printf("%d\n", var);  // It seemingly works!

我还做了一个实验，具体如下.

int var = 0;
// the variable var's address is 0x7fffffffe4a4 now in my system
unsigned long long ull = 0x7fffffffe4a4;  
int *ptr = &var;

// First, I want to know whether the memory used by unsigned long long and the one used by a pointer differ
printf("%zu\n", sizeof(ull));  
printf("%zu\n", sizeof(ptr));
// The results are both "8" in my system
// Next I try to assign two different values to var by two ways
scanf("%d", ull);  // I try to use x as an address to assign var
printf("%d\n", var);
scanf("%d", ptr);  // And I also use a normal pointer to assign var
printf("%d\n", var);
// The results were in line with expectations!

看起来unsigned long long变量可以成功地用作指针(尽管编译器警告我参数应该是int*而不是unsigned long long)，我想知道…

在硬件级别上，变量和指针有什么不同？这两种类型的对象在存储和使用时是如何处理的？由谁处理这些对象？是否建议执行上述操作？

(归根结底，这是c的一个特性吗？)