Wiki User
∙ 15y ago2 017 036
Wiki User
∙ 15y ago2014 ( The sum of the digits = 7, a prime number )
Add all the digits of the number together - if the sum of the digits is divisible by 9, then the original number is too.
Add together all the digits in the odd positions in the number. Sum = A Add together all the digits in the even positions in the number. Sum = B If A-B is 0 or if it divisible by 11 (positive or negative), then the original number is divisible by 11.
1 + 2 + 3... + n = n (n + 1) ----------- 2 1 + 2 + 3... + 2008 = 2,017,036 (see below) 2008 (2008 + 1) -------------------------- 2 Just take the highest number (2008 in your case) and multiply it by itself plus one, so ...(2008 + 1), and divide the entire quantity by 2.
It you add up all the digit in the number they will total 11. For example the number 425 has digits that sum to 11. (4 + 2 + 5 = 11)
I'm so sure you meant "odd" digits, I'm going to answer it as if you did. -- If they all have to be different digits, then it's 13,579 or .13579 . -- If they don't have to be all different, then it's 11,111 or .11111 .
if it's even and all the digits add up to a multiple of 3
537
804
If all digits show up from an international call, you add to the normal number the country code.
10
If you add all the digits up, and the total equals a number that 3 can go in, then it's a factor of 3.