Problem Statement

A positive integer n is said to be a Rhonda number to base b if the product of the base b digits of n is equal to b times the sum of n's prime factors.

These numbers were named by Kevin Brown after an acquaintance of his whose residence number was 25662, a member of the base 10 numbers with this property.

25662 is a Rhonda number to base-10. The prime factorization is 2 × 3 × 7 × 13 × 47; the product of its base-10 digits is equal to the base times the sum of its prime factors: 2 × 5 × 6 × 6 × 2 = 720 = 10 × (2 + 3 + 7 + 13 + 47) Rhonda numbers only exist in bases that are not a prime. Rhonda numbers to base 10 always contain at least 1 digit 5 and always contain at least 1 even digit.

Let's start with the solution:

func is_rhonda_number(n, base = 10) {
    base.is_composite || return false
    n > 0             || return false
    n.digits(base).prod == base*n.factor.sum
}

for b in (2..16 -> grep { .is_composite }) {
    say ("First 10 Rhonda numbers to base #{b}: ",
        10.by { is_rhonda_number(_, b) })
}