A number n is called wasteful if the number of digits in the prime factorization of n (including powers) uses more digits than the number of digits in n. The first few wasteful numbers are 4, 6, 8, 9, 12, 18, 20, 22, 24 ... (OEIS A046760). A number that is not wasteful is called a frugal number (Pinch).

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