Today is Sunday. If tomorrow is the first day, what day is 1 ^ 3 + 2 ^ 3 + 3 ^ 3 +. + 1998 ^ 3?

Today is Sunday. If tomorrow is the first day, what day is 1 ^ 3 + 2 ^ 3 + 3 ^ 3 +. + 1998 ^ 3?

It's a multiple of seven, so it's Monday
The formula of cubic sum is 1 ^ 3 + 2 ^ 3 +... + n ^ 3 = [n (n + 1) / 2] ^ 2