If $σ_k(n)$= Sum of kth powers of all the positive divisors of n, n ∈ N, the what is the value of $σ_3(4)$ ?
Answer & explanation
Correct answer: option 3
The correct answer is option (3) : 73
$σ_3(4)$
Positive divisions of 4 are $ 1, 2, 4$
$∴σ_2(12)= 1^3+2^3+4^3$
$=1+8+64$
$=73$