999999999999
12
999 999 999 990
100000000000
If repeated digits are allowed, then the largest 12-digit number is 999,999,999,999 .If repeated digits are not allowed, then the largest 12-digit number is 989,898,989,898 .If the same digit can't be used more than once, then the largest possible number has only10 digits. The number is 9,876,543,210 .
999999999999
12
999 999 999 990
930
No 5 digit number can equal 12 and so there can be no answer to the question.
100000000000
If repeated digits are allowed, then the largest 12-digit number is 999,999,999,999 .If repeated digits are not allowed, then the largest 12-digit number is 989,898,989,898 .If the same digit can't be used more than once, then the largest possible number has only10 digits. The number is 9,876,543,210 .
999,799,949,899
-9
How about: 960
BBB which, in decimal, is equal to 1727 (= 123 - 1)
100,000,000,009 or .000000000009