Elementary Theory of Numbers
by Waclaw Sierpinski
Publisher: ICM 1964
Number of pages: 516
The variety of topics covered here includes divisibility, diophantine equations, prime numbers (especially Mersenne and Fermat primes), the basic arithmetic functions, congruences, the quadratic reciprocity law, expansion of real numbers into decimal fractions, decomposition of integers into sums of powers, some other problems of the additive theory of numbers and the theory of Gaussian integers.
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by William Stein - Springer
Textbook on number theory and elliptic curves. It discusses primes, factorization, continued fractions, quadratic forms, computation, elliptic curves, their applications to algorithmic problems, and connections with problems in number theory.
by R. D. Carmichael - John Wiley & Sons
The purpose of this book is to give the reader a convenient introduction to the theory of numbers. The treatment throughout is made as brief as is possible consistent with clearness and is confined entirely to fundamental matters.
by Allen Hatcher - Cornell University
An introductory textbook on elementary number theory from a geometric point of view, as opposed to the strictly algebraic approach. A fair amount of the book is devoted to studying Conway's topographs associated to quadratic forms in two variables.
by Thomas Taylor, A. J. Valpy
The substance of all that has been written on this subject by Nicomachus, Iamblichus, and Boetius, together with some particulars respecting perfect, amicable, and other numbers, which are not to be found in the writings of modern mathematicians.