Possible Upper Bound of Sum of Divisors

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Let $\sigma(n)$ be the sum of all divisors of $n$ (including $1$ and $n$). Is this function, $$f(x)=(e^\gamma(n+1))\ln(\ln n)+\ln(e^\gamma n)$$ an upper bound of $\sigma(n)$ for sufficiently large $n$? If so, how large must $n$ be to be "sufficiently large"?