Prime factors → counting

Divisors — exponents (e+1) product.

Try this in Python

def divisor_count(factors):
    prod = 1
    for _, e in factors:
        prod *= e + 1
    return prod

print(divisor_count([(2, 3), (3, 1)]))

Key takeaways

• Unique factorization.
• Ordered vs unordered.
• Modulo.