Can you find a pattern and find the missing number in the series given below?
84, 155, 258, ? , 584, 819.
399
4^3 + 3^2 + 4 = 84
5^3 + 5^2 + 5 = 155
6^3 + 6^2 + 6 = 258
8^3 + 8^2 + 8 = 584
9^3 + 9^2 + 9 = 819
Therefore the missing number is:
7^3 + 7^2 + 7 = 399.
