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# Wasteful Number

A number is called wasteful if the number of digits in the prime factorization of (including powers) uses more digits than the number of digits in . 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).

Economical Number, Equidigital Number, Evil Number, Frugal Number, Happy Number, Lucky Number, Odious Number, Unhappy Number

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## References

Pinch, R. G. E. "Economical Numbers." http://www.chalcedon.demon.co.uk/publish.html#62.Rivera, C. "Problems & Puzzles: Puzzle 053-Sequences of Consecutive Economical Numbers." http://www.primepuzzles.net/puzzles/puzz_053.htm.Santos, B. R. "Problem 2204. Equidigital Representation." J. Recr. Math. 27, 58-59, 1995.Sloane, N. J. A. Sequence A046760 in "The On-Line Encyclopedia of Integer Sequences."

Wasteful Number

## Cite this as:

Weisstein, Eric W. "Wasteful Number." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/WastefulNumber.html