Problem 57288. Sum the unitary divisors of a number

Cody Problems 1933 and 46898 deal with sigma(n), the sum of divisors function. This problem deals with sigma*(n), the sum of unitary divisors functions. Unitary divisors are defined in Cody Problem 56738, which asks for a list of the unitary divisors of a number, and they appear in Cody Problem 56743, which asks for a count.
Write a function to sum the unitary divisors of a number. For example, the unitary divisors of 18 are 1, 2, 9, and 18; therefore, the sum is 30.
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90.91% Correct | 9.09% Incorrect
Last Solution submitted on Dec 07, 2025

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number theory sequence

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