Amazing Number 9

The number nine has always fascinated me. Multiplication always reduces down to 9. Divide by 2 unlimited times always also reduces to 9. Circles break down to 9 in two different ways. Plus there are several mathematic unique aspects of 9.

When you multiply any number by 9, then add the resulting digits and the value always reduces down to 9. For example, 5 x 9 = 45, reduce 45 to a single digit by adding them together: 4 + 5 = 9. Similarly, 8 x 9 = 72, and 7 + 2 = 9. Or 34 x 9 = 306, 3 + 0 + 6 = 9, and so forth. Try this with any number for yourself, even with decimals like 23.4 x 9 = 210.6 and 2 + 1 + 0 + 6 = 9. Same thing happens if you add any number to 9, it always reduced down to the original number. For example 4 plus 9 = 13 which reduces to 4.

Likewise, divide 9 by 2 equals 4.5 and 4 + 5 = 9.  Divide 4.5 by 2 for 2.25 and 2 + 2 + 5 = 9.  Divide 2.25 by 2 for 1.125 and 1 + 1 + 2 + 5 = 9.  And so forth.

Circles are interesting with their 360 degrees.  Of course 3 + 6 + 0 = 9.  Split circle in half and you have 180 degrees (1 + 8 + 0 = 9). Split circle into fourths for 90 degrees, obviously reduces to 9. Split into eights to 45 degrees (4 + 5 = 9). Continue splitting to 22.5 degrees, 11.25 degrees, 5.625 degrees. The resulting angle always reduces to 9 no matter how many times.

Put any polygon that touches all edges into a circle and the vectors always add up to 9. Triangle of 60 + 60 + 60 equals 180 reduces to 9. Square is 90 times 4. Hexagram is 120 degrees time 6 = 720 which reduces to 9.  See See “Nikola tesla. Why did Tesla say that 3,6,9 was the key to the universe?” for full presentation.

Interestingly, 1+2+3+4+5+6+7+8= 36 which reduces to 9.

Nine is a Motzkin number. It is the first composite lucky number (in number theory, a lucky number is a natural number in a set which is generated by a certain “sieve"), along with the first composite odd number and only single-digit composite odd number.

9 is the only positive perfect power that is one more than another positive perfect power, by Mihăilescu's Theorem.

9 is the highest single-digit number in the decimal system.  It is the second non-unitary square prime of the form (p2) and the first that is odd.

No other number has these qualities. Check Wikipedia for more information.

If you are into numerology, the “Expression" meaning of the number 9 is:

You are the humanitarian, filled with great compassion and idealism -- your deepest intention is to transform the world. You realize your greatest satisfaction when you are involved in an activity that directly benefits the public good. Politics, law, environmental protection, teaching, and healing are areas in which you would succeed.

You are not shackled with prejudice; in fact, a wide diversity of people and experiences brings forth qualities in you that would otherwise lay dormant. Despite the cool, distant personality you project, people are attracted to you. But while you are a loving and sincere person, you don't often express what you truly feel. You are not a very good judge of character, yet your basic belief in the goodness of humanity is unshakeable.

And in summary, that is why I have never aspired to be the number one wizard.

I am Wizard #9.