"The Great Story of Numbers" is a new, free book that provides a comprehensive introduction to elementary number theory. The book starts from the nature of numbers and mathematical induction, then develops counting, integers, number representations, divisibility, linear Diophantine equations, congruences and modular arithmetic, the Chinese Remainder Theorem, rational numbers and continued fractions, Pythagorean triples, and infinite descent. It then moves into prime numbers and the Fundamental Theorem of Arithmetic, multiplicative functions, Fermat's Little Theorem, Euler's and Wilson's theorems, Fermat's Two-Squares Theorem, Gaussian integers, polynomials, primitive roots, discrete logarithms, polynomial congruences, cyclotomic polynomials, quadratic residues, Legendre symbols, quadratic reciprocity, and much more. It's a useful resource if you want to study number theory from its foundations and gradually move toward more advanced topics. The current edition is almost 500 pages long. egbertrijke.github.io/elemen…