The book "Problem-workshop on number theory", written by outstanding scientists Alexandrov V. A. and Gorshenin S. M. It is a unique manual that not only deepens the reader's knowledge in the field of number theory, but also develops analytical thinking through solving practical problems. This edition will be a real find for students, graduate students and anyone interested in mathematics at a deeper level. Number theory is one of the most fascinating and mysterious areas of mathematics, studying the properties of integers. In the book, the authors offer readers a wide range of tasks that cover both classical and modern aspects of number theory. Each problem is accompanied by a detailed solution and explanation, which allows not only to test their knowledge, but also to understand how to approach the solution of certain mathematical problems. Who can like this tasker? First of all, this edition will be useful for students of mathematical and physical faculties, as well as for schoolchildren who are passionate about mathematics and preparing for the Olympiads . However, the book will be interesting to a wider audience - everyone who wants to develop their logical abilities and learn to think outside the box. If you like to solve puzzles and look for solutions to complex problems, then the “Number Theory Practitioner” will be a real challenge for you and a source of inspiration. The book raises many important topics, such as the properties of prime numbers, divisibility, Fermat's theorem, and many others. The authors not only offer solutions, but also explain how number theory can be applied in various fields of science and technology. This makes the book particularly relevant in today's world, where mathematics plays a key role in the development of technology and scientific research. The style of Alexandrov and Gorshenin is clear and accessible, which allows the reader to easily assimilate even the most complex concepts. Both authors have extensive experience in teaching and scientific work, which is reflected in their approach to the presentation of the material. There are already many well-known publications in their arsenal, and this task book will not be an exception, but rather complement their portfolio, offering readers a high-quality and up-to-date guide. If you are looking for books like The Number Theory Practitioner, then you should pay attention to such works as Gauss's Theory of Numbers or Gauss's Theory of Numbers.