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Aptitude Number System

Divisibility and remainders and primes and HCF LCM and digit tricks in one guided course.

Created by INVOCLIENT

Last updated 9/2026English
17lessons
174minutes
65problems
Number System course cover

Free forever

  • 17 lessons with shortcuts
  • 65 GATE level problems
  • Session based progress
  • Mobile friendly lessons

What you will learn

  • Classify numbers and spot rational versus irrational forms
  • Sum series and squares and cubes with closed forms
  • Test primes and count coprimes with Euler totient
  • Crack remainders with Euler and Fermat and Wilson
  • Count divisors and compute HCF LCM and digit sums
  • Extract units and last two digits of giant powers
  • Apply divisibility and base rules in seconds
  • Floor values and 1001 tricks and factorial powers

Syllabus

17 lessons
1
Classification of Numbers14 min and 6 parts and 4 problems
Open
2
Sum of Number Series10 min and 4 parts and 4 problems
Open
3
Rational Numbers Deep Dive12 min and 3 parts and 4 problems
Open
4
Prime and Composite Numbers11 min and 2 parts and 4 problems
Open
5
Co-primes10 min and 2 parts and 4 problems
Open
6
Special Numbers12 min and 3 parts and 4 problems
Open
7
Properties of 10016 min and 2 parts and 3 problems
Open
8
Remainders14 min and 5 parts and 4 problems
Open
9
Theorems on Remainders13 min and 4 parts and 4 problems
Open
10
Divisors of a Number12 min and 3 parts and 4 problems
Open
11
Finding Units Digit8 min and 3 parts and 4 problems
Open
12
Finding Last Two Digits10 min and 3 parts and 4 problems
Open
13
Powers in Factorials7 min and 2 parts and 4 problems
Open
14
Divisibility Rules11 min and 3 parts and 4 problems
Open
15
HCF and LCM12 min and 3 parts and 4 problems
Open
16
Digit-Sum Rule7 min and 2 parts and 3 problems
Open
17
Greatest Integer Function5 min and 1 parts and 3 problems
Open