1. Some Popular Interesting ,Mysterious and Amazing Numbers in Mathematics

**1.Ramanujan No. : 1729**

Almost everyone knows about this number. This is the smallest number. Which can be expressed in 2 different ways as the sum of 2 different cubes.

1729 = 10^3 + 9^3 =12^3 + 1^3

*Interesting story behind the number 1729*

**Professor GH Hardy once visited Ramanujan when he was hospitalized after several ailments.**

**Hardy pointed out at random that he had come in a taxi that had the number 1729 on it which seemed too dull and ordinary to him.**

**Upon hearing this, Ramanujan immediately indicated without any second thought that 1729 was indeed a special number.**

**He observed that 1729 is the smallest number that can be represented as the sum of two cubes in two different ways.**

1729 =10^3 + 9^3 = 12^3 +1^3

**This story is very famous among mathematicians. 1729 is called the Ramanujan-Hardy number”.**

**2.Kaprekar’s Constant. : 6174**

6174 is known as Kaprekar’s constant after the Indian mathematician D. R. Kaprekar

**This number can be obtained by this rule:**

- Take any four-digit number, using at least two distinct digits (leading zeros are allowed).
- Arrange the digits in descending order and then in ascending order, adding leading zeros, if necessary, to get two four-digit numbers.
- Subtract the smaller number from the larger number.
- Go back to step 2 and repeat.

This rule will always reach its fixed point, 6174, in at most 7 iterations. **For example, let’s take the number 1008**

8100 – 0018 = 8082

8820 – 0288 = 8532

8532 – 2358 = **6174**

7641 – 1467 = **6174**

**3. π**

is a mathematical constant that is the ratio of the circumference of a circle to its diameter, approximately equal to 3.14159. The number appears in many formulas in mathematics and physics. π is irrational number

It is a transcendental number, which means that it cannot be a solution to an equation consisting only of powers, products, sums and integers.

It is impossible to draw a square equal to the area of a circle with a compass and straightedge because π is transcendental

**4. The Pingala sequence **Or** Matra Meru**

Matra Meru sequence, in which each number is the sum of the two preceding numbers. The sequence usually begins with 0 and 1. Starting with 0 and 1, the next few values in the sequence are:

**0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811, …**

Matra Meru Spiral

When we make squares with those widths, we get a nice spiral:

This spiral is found in nature!

If we take any two successive numbers in the sequence, their ratio gets closer to 1.618 What we call the golden ratio:

3 / 2 = **1**.5

13 / 8 = **1.6**66

55 / 34 = **1.61**764

233 / 144 = **1.6180**5

…

317,811 / 196,418 = **1.61803**

**watch this video**

**Video 1**

Fibonacci Number – Is it a Hindu number used in Ancient India? Secret of Life | Praveen Mohan |

**Video 2**

Golden Ratio? ‘Mrityunjaya’ – The Key To Life | Ancient Indian Secret of Vedas | Praveen Mohan

**5.1089**

Take a 3-digit number made up of different elements (For Example 108).

Subtract the smallest possible number from the chosen 3 digits from the largest possible number to be formed. In our case, it is 810–018 = 792.

Take the answer and reverse it. Now, we have 297.

Lastly, add the inverse number 297 to the result 792 which will always give us 1089.

**6.108 – The Secret of Life- By Praveen Mohan**

108 – PART II . Ancient Design Revealed?- By Praveen Mohan

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