What mathematical operations does this code perform?

Question

JavaScript

There is JavaScript code:

function o(e) {
                    var t = arguments.length
                      , n = e & 65535
                      , r = e >> 16;
                    for (var i = 1; i < t; i++) {
                        var s = arguments[i];
                        n += s & 65535,
                        r += (s >> 16) + (n >> 16),
                        n &= 65535
                    }
                    return r << 16 | n & 65535
                }

I’ve been studying it for the second hour and I can’t understand what specific operations it performs - I don’t understand the operators |, >> and &. If you pass in it, for example, the number 100000000000000000000, it will return 1661992960.
How does this algorithm work?

Answer 1

they are logical and bitwise operations.
| - logical addition
& - logical multiplication
<< and >> - shift left or right by the number of bits, similar to multiplying or dividing by 2 to the specified degree
specifically how &
y = x & 65535
for x=12345
translate into binary form
11000000111001
translate 65535 there
1111111111111111
perform logical bitwise addition (look for the rules yourself)
result = 10011000000111000
translate back into decimal form
77880 something
like this)

Answer 2

what specific operations does it perform

bitwise