Total of all digits from one to a million

Add up every digit of every integer from $1$ to $1{,}000{,}000$ inclusive. (For instance, $46$ contributes $4+6=10$.) What is the total?

$27{,}000{,}001$. Pad $0$ to $999999$ to six digits: each position runs through $0$–$9$ equally often, so each digit appears $100{,}000$ times per position, giving $6\times45\times100{,}000=27{,}000{,}000$. Adding $1$ for the number $1{,}000{,}000$ gives the total.