Good books on arithmetic functions? As I was studying the Möbius $\mu$ function and Gram series,
I got myself some pretty nice books:
Ribenboim - The New Book of Prime Number Records
Apostol - Introduction to Analytic Number Theory
Niven, Zuckerman, Montgomery - An Introduction to the Theory of Numbers
Iwaniec and Kowalski - Analytic Number theory
All of them deal with the Möbius $\mu$ function.
But none of them dealt with the subject in details other than giving a few theorems and problems...
So I would like to know, If you guys know of some good books that deal exclusively with arithmetic functions?
 A: Isn't it weird that nobody's mentioned so far Chandrasekharan's treatise on arithmetic functions? OK, they've already mentioned his book on the principles of analytic number theory, yet the book I'm now referring to is
K. Chandrasekharan. Arithmetical functions. Die Grundlehren der Mathematischen Wissenschaften (Band 167), Springer Verlag, 1970.
You should definitely take a look at it, esteemed rpg16!
A: A MathSciNet search set to Books and with "arithmetic functions" entered into the "Anywhere" field yields 148 matches.  Some of the more promising ones:

The theory of arithmetic functions.
  Proceedings of the Conference at Western Michigan University, Kalamazoo, Mich., April 29--May 1, 1971. Edited by Anthony A. Gioia and Donald L. Goldsmith. Lecture Notes in Mathematics, Vol. 251. Springer-Verlag, Berlin-New York, 1972. v+287 pp. 

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Narkiewicz, Wƚadysƚaw Elementary and analytic theory of algebraic numbers. Monografie Matematyczne, Tom 57. PWN---Polish Scientific Publishers, Warsaw, 1974. 630 pp. (errata insert).

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Babu, Gutti Jogesh
  Probabilistic methods in the theory of arithmetic functions.
  Macmillan Lectures in Mathematics, 2. Macmillan Co. of India, Ltd., New Delhi, 1978.

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Elliott, P. D. T. A. Arithmetic functions and integer products. Grundlehren der Mathematischen Wissenschaften [Fundamental Principles of Mathematical Sciences], 272. Springer-Verlag, New York, 1985. 

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Sivaramakrishnan, R. Classical theory of arithmetic functions. Monographs and Textbooks in Pure and Applied Mathematics, 126. Marcel Dekker, Inc., New York, 1989.

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Schwarz, Wolfgang; Spilker, Jürgen Arithmetical functions. An introduction to elementary and analytic properties of arithmetic functions and to some of their almost-periodic properties. London Mathematical Society Lecture Note Series, 184. Cambridge University Press, Cambridge, 1994.

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Tenenbaum, Gérald Introduction to analytic and probabilistic number theory. Translated from the second French edition (1995) by C. B. Thomas. Cambridge Studies in Advanced Mathematics, 46. Cambridge University Press, Cambridge, 1995.

A: There's also this one: McCarthy, Paul J. Introduction to arithmetical functions. Springer, 1986.
A: (As I can't comment)
If you understand German, Springer published last year a translated version of Paul McCarthy's book - "Arithmetische Funktionen" (ISBN: 978-3-662-53731-2).
