How to sum over a big vector in Julia

I am trying to take the sum of a very "big" vector, I know the big() function can be used for calculating large number,
which I even used down below (and it works). However, if I try to use it in a sum it doesn't work.
I tried both big(sum(test, dims=1)) and sum(big(test), dims=1)) but I recieve following error:
InexactError: Int64(-3331427209747016990720)

test   = Tuple{Int, Int}[]
N = 80
Iterations = 60

for i in 1:10000
       push!(test, (big(largeNumber1(N, Iterations)) * big(largeNumber2(N, Iterations)), 0))        
end 

# this just transforms test into a vector
test = hcat(first.(test), last.(test)) * [1, 0]

sum(test, dims=1) # here is where the code "breaks"


<output> 1-element Vector{Int64}:
         -5233167026984513820

Most likely I am using big() wrong