How many integers between 1 and 10^19 are such that the sum of their digits is 2?  Select
A) 190
B) 210
C) 211
D) 230
E) 231
The integers with a sum of 2 are:   2, 20, 200,...,2*10^18 and there are 19 integers in this list.   Also, these integers have a sum of 2:   11   101, 110   1001, 1010, 1100   etc...   The number of integers in this list is 1 + 2 + ... + 18   Thus, the total number of integers is 1 + 2 + ... + 18 + 19 = 20*19/2= 
<gadget id="calculator">20*19/2</gadget>
<output>190</output>
190   The answer is 190.
<result>A</result>
How many integers between 1 and 10^19 are such that the sum of their digits is 2?