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June 2020 - Solution
The solution is 9,099,305,265,787,740,660,101,533,112,532,340,984,145,268. This number can be found by finding the preimage of the Euler totient function on 3,031,634,148,236,289,733,373,855,928,919,180,891,127,808, and computing the sum of divisors for each element of the preimage. All this can be accomplished relatively easily given the prime factorization of the numbers involved. See "Euler's Totient Function and Its Inverse" by Hansraj Gupta for additional details.
This number is Oded's way of welcoming me, as it turns out this is the ASCII encoding of “https://gadial.net”, the link to my (Hebrew) math blog. Thanks, Oded, and farewell!