Numerical properties of 191

July 2024 · 7 minute read
Image to Crop

Show numerical properties of 191

We start by listing out divisors for 191

DivisorDivisor Math
1191 ÷ 1 = 191
Positive or Negative Number Test:
Positive Numbers > 0

Since 191 ≥ 0 and it is an integer
191 is a positive number

Whole Number Test:
Positive numbers including 0
with no decimal or fractions

Since 191 ≥ 0 and it is an integer
191 is a whole number

Prime or Composite Test:

Since 191 is only divisible by 1 and itself
it is a prime number

Perfect/Deficient/Abundant Test:

Calculate divisor sum D

If D = N, then it's perfect

If D > N, then it's abundant

If D < N, then it's deficient

Divisor Sum = 1

Since our divisor sum of 1 < 191
191 is a deficient number!

Odd or Even Test (Parity Function):

A number is even if it is divisible by 2
If not divisible by 2, it is odd

95.5  =  191
  2

Since 95.5 is not an integer, 191 is not divisible by
it is an odd number

This can be written as A(191) = Odd

Evil or Odious Test:

Get binary expansion

If binary has even amount 1's, then it's evil

If binary has odd amount 1's, then it's odious

191 to binary = 10111111

There are 7 1's, 191 is an odious number

Triangular Test:

Can you stack numbers in a pyramid?
Each row above has one item less than the row before it

Using a bottom row of 20 items, we cannot form a pyramid
191 is not triangular

Triangular number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Rectangular Test:

Is there an integer m such that n = m(m + 1)

No integer m exists such that m(m + 1) = 191
191 is not rectangular

Rectangular number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Automorphic (Curious) Test:

Does n2 ends with n

1912 = 191 x 191 = 36481

Since 36481 does not end with 191
it is not automorphic (curious)

Automorphic number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Undulating Test:

Do the digits of n alternate in the form abab

In this case, a = 1 and b = 9

In order to be undulating, Digit 1: 111 should be equal to 1

In order to be undulating, Digit 2: 999 should be equal to 9

In order to be undulating, Digit 3: 111 should be equal to 1

Since all 3 digits form our abab undulation pattern
191 is undulating

Square Test:

Is there a number m such that m2 = n?

132 = 169 and 142 = 196 which do not equal 191

Therefore, 191 is not a square

Cube Test:

Is there a number m such that m3 = n

53 = 125 and 63 = 216 ≠ 191

Therefore, 191 is not a cube

Palindrome Test:

Is the number read backwards equal to the number?

The number read backwards is 191

Since 191 is the same backwards and forwards
it is a palindrome

Palindromic Prime Test:

Is it both prime and a palindrome

From above, since 191 is both prime and a palindrome
it is a palindromic prime

Repunit Test:

A number is repunit if every digit is equal to 1

Since there is at least one digit in 191 ≠ 1
then it is NOT repunit

Apocalyptic Power Test:

Does 2n contain the consecutive digits 666?

2191 = 3.1385508676933E+57

Since 2191 does not have 666
191 is NOT an apocalyptic power

Pentagonal Test:

It satisfies the form:

n(3n - 1)
2

Check values of 11 and 12
Using n = 12, we have:
12(3(12 - 1)
2

12(36 - 1)
2


210 ← Since this does not equal 191
this is NOT a pentagonal number

Using n = 11, we have:
11(3(11 - 1)
2

11(33 - 1)
2


176 ← Since this does not equal 191
this is NOT a pentagonal number

Pentagonal number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Hexagonal Test:

Is there an integer m such that n = m(2m - 1)

No integer m exists such that m(2m - 1) = 191
Therefore 191 is not hexagonal

Hexagonal number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Heptagonal Test:

Is there an integer m such that:

m  =  n(5n - 3)
  2

No integer m exists such that m(5m - 3)/2 = 191
Therefore 191 is not heptagonal

Heptagonal number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Octagonal Test:

Is there an integer m such that n = m(3m - 3)

No integer m exists such that m(3m - 2) = 191
Therefore 191 is not octagonal

Octagonal number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Nonagonal Test:

Is there an integer m such that:

m  =  n(7n - 5)
  2

No integer m exists such that m(7m - 5)/2 = 191
Therefore 191 is not nonagonal

Nonagonal number:

1st  

2nd  

3rd  

4th  

5th  

6th  

7th  

8th  

9th  

10th  

Tetrahedral (Pyramidal) Test:

Tetrahederal numbers satisfy the form:

n(n + 1)(n + 2)
6

Check values of 9 and 10
Using n = 10, we have:
10(10 + 1)(10 + 2)
6

10(11)(12)
6

220 ← Since this does not equal 191
This is NOT a tetrahedral (Pyramidal) number

Using n = 9, we have:
9(9 + 1)(9 + 2)
6

9(10)(11)
6

165 ← Since this does not equal 191
This is NOT a tetrahedral (Pyramidal) number

Narcissistic (Plus Perfect) Test:

Is equal to the square sum of it's m-th powers of its digits

191 is a 3 digit number, so m = 3

Square sum of digitsm = 13 + 93 + 13

Square sum of digitsm = 1 + 729 + 1

Square sum of digitsm = 731

Since 731 <> 191
191 is NOT narcissistic (plus perfect)

Catalan Test:
Cn  =  2n!
  (n + 1)!n!

Check values of 6 and 7
Using n = 7, we have:
C7  =  (2 x 7)!
  7!(7 + 1)!

Using our factorial lesson

C7  =  14!
  7!8!

C7  =  87178291200
  (5040)(40320)

C7  =  87178291200
  203212800

C7 = 429

Since this does not equal 191
This is NOT a Catalan number

Using n = 6, we have:
C6  =  (2 x 6)!
  6!(6 + 1)!

Using our factorial lesson

C6  =  12!
  6!7!

C6  =  479001600
  (720)(5040)

C6  =  479001600
  3628800

C6 = 132

Since this does not equal 191
This is NOT a Catalan number

Number Properties for 191
Final Answer

Positive
Whole
Prime
Deficient
Odd
Odious
Undulating
Palindrome
Palindromic Prime

You have 1 free calculations remaining


What is the Answer?

Positive
Whole
Prime
Deficient
Odd
Odious
Undulating
Palindrome
Palindromic Prime

How does the Number Property Calculator work?

Free Number Property Calculator - This calculator determines if an integer you entered has any of the following properties:
* Even Numbers or Odd Numbers (Parity Function or even-odd numbers)
* Evil Numbers or Odious Numbers
* Perfect Numbers, Abundant Numbers, or Deficient Numbers
* Triangular Numbers
* Prime Numbers or Composite Numbers
* Automorphic (Curious)
* Undulating Numbers
* Square Numbers
* Cube Numbers
* Palindrome Numbers
* Repunit Numbers
* Apocalyptic Power
* Pentagonal
* Tetrahedral (Pyramidal)
* Narcissistic (Plus Perfect)
* Catalan
* Repunit
This calculator has 1 input.

What 5 formulas are used for the Number Property Calculator?

Positive Numbers are greater than 0
Whole Numbers are positive numbers, including 0, with no decimal or fractional parts
Even numbers are divisible by 2
Odd Numbers are not divisible by 2
Palindromes have equal numbers when digits are reversed

For more math formulas, check out our Formula Dossier

What 11 concepts are covered in the Number Property Calculator?

divisora number by which another number is to be divided.evennarcissistic numbersa given number base b is a number that is the sum of its own digits each raised to the power of the number of digits.numberan arithmetical value, expressed by a word, symbol, or figure, representing a particular quantity and used in counting and making calculations and for showing order in a series or for identification. A quantity or amount.number propertyoddpalindromeA word or phrase which reads the same forwards or backwardspentagona polygon of five angles and five sidespentagonal numberA number that can be shown as a pentagonal pattern of dots.
n(3n - 1)/2perfect numbera positive integer that is equal to the sum of its positive divisors, excluding the number itself.propertyan attribute, quality, or characteristic of something

Example calculations for the Number Property Calculator

Number Property Calculator Video


Tags:

Add This Calculator To Your Website

ncG1vNJzZmivp6x7rq3ToZqepJWXv6rA2GeaqKVfpbKzssScq2eomKWMr8HManRkaWlmc7G4nIyfqK9bg8KusdGimpqkW4W%2FsLzEq6uinaM%3D