6 × 12345678900987654321 = 74074073405925925926
12345678900987654321
12345678900987654321
66 = 46656 67 = 279936
6x6x6x6x6= 7776
6 x 6 x 6 x 6 x 6 x 6 x 6 x 6 = 68 = 1679616
5 6
65
65 (there are five 6's)
2 times 3 = 6 or 1 times 6 = 6
6 times 6 times 5 equals 180.
The answer is 12345678900987654322. Simply add the numbers together arithmetically as you would for the problem two plus two. To check your work, a calculator is the best option.
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