(22222222)3=2×30+2×3 1+2×32+2×33+2×34+2×35+2×36+2×37=6560,

∵6560=8×90+8×9 1+8×9 2+8×93

The result of converting ternary number (2222222)3 into decimal number is 8888(9).

So the answer is: 8888(9)