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Library/Number Theory

Number Theory

Practice
Overview

Divisibility, primes, modular arithmetic, Diophantine equations

Practice
Junior Mathematical Challenge 2021
Junior Mathematical Challenge 2020
Fill the digit to make divisible by 3
Make 15 divisible by 15
Junior Mathematical Challenge 2023
Question 3
Junior Mathematical Challenge 2021
55*44* divisible by 72
Find digits in 35!
Digital root of 100!
More practice problems →

Deeper topics

  • Arithmetic functions
  • Diophantine Approximation
  • Diophantine Equations
  • Divisibility of numbers. General properties
  • Divisibility rules
  • Division with remainder. Arithmetic of remainders
  • Equations in integers
  • GCD and LCM. Mutual primality
  • Modular Arithmetic
  • Number theory. Divisibility (other)
  • Parity
  • Prime factorisation
  • Prime Numbers
  • Prime numbers and their properties
  • Products and factorials
Practice
Junior Mathematical Challenge 2021
Junior Mathematical Challenge 2020
Fill the digit to make divisible by 3
Make 15 divisible by 15
Junior Mathematical Challenge 2023
Question 3
Junior Mathematical Challenge 2021
55*44* divisible by 72
Find digits in 35!
Digital root of 100!
More practice problems →

Deeper topics

  • Arithmetic functions
  • Diophantine Approximation
  • Diophantine Equations
  • Divisibility of numbers. General properties
  • Divisibility rules
  • Division with remainder. Arithmetic of remainders
  • Equations in integers
  • GCD and LCM. Mutual primality
  • Modular Arithmetic
  • Number theory. Divisibility (other)
  • Parity
  • Prime factorisation
  • Prime Numbers
  • Prime numbers and their properties
  • Products and factorials