TITLE: Limit of ratios of numbers with $m$ factors and primes
QUESTION [8 upvotes]: This is my first question. 
Let $a_1, a_2,\ldots, a_k$ be natural numbers $\leq n$ with $m$ prime factors.
Let $p_1, p_2, \ldots, p_r$ be the prime numbers $\leq n$. 
Let $$C_{m,n} = \frac{\sum_{i=1}^{k}a_i}{\sum_{i=1}^{r}p_i}$$
Does the following limit exist when $m\geq 2$? Obviously, when $m=1$,  $C_{1,n}=1$.
$$\lim_{n\to \infty} C_{m,n}$$
I have some guesses but not defendable enough.
My best,
The FM.

REPLY [4 votes]: For $m\gt1$, there are more numbers with $m$ prime factors than there are primes, in the following sense: 
Hardy and Wright, Theorem 437, prove that the number of integers up to $x$ with exactly $m$ prime factors (and it doesn't matter whether the primes are distinct or not) is asymptotic to $${x(\log\log x)^{m-1}\over(m-1)!\log x}$$ They attribute the result to Landau, 1900. Now the number of primes is asymptotic to $x/(\log x)$, so the ratio is $(\log\log x)^{m-1}/(m-1)!$, which of course goes to infinity with $x$. 
Meanwhile, the sum of the primes up to $x$ is asymptotically $x^2/(2\log x)$ although I haven't found a wholly trustworthy cite for this. I'm sure  (although I'm not up to proving it) that the sum of the almost-primes will be bigger by that same factor of $(\log\log x)^{m-1}/(m-1)!$