New largest prime discovered $2^{74\,207\,281}-1$

New largest prime discovered 

$$\Huge2^{74\,207\,281}-1$$

Recall a prime number is one which is only divisible by itself and $1$ and the smallest prime numbers are $2,3,5,7,11,13,17,...$.

The new largest prime number has got over $22$ million digits! that's right!
The number $1\,000\,000$ has $7$ digits! Can you imagine a number with $22$ million digits!
A book may have say $2000$ characters to a page, so that's about $22\,000\,000\div 2000=11\,000$ pages just to write out the number long hand!

PHYS.ORG

Euler's Formula for Simple Polyhedras $F+V-E=2$

Definition: 
A SIMPLE POLYHEDRON is a polyhedron which has no holes.

THEOREM:
Euler's Formula for Simple Polyhedra. 
If $V$ is the number of vertices, $E$ the number of edges, and $F$ the number of faces of a simple polyhedron, then $$F+V-E=2$$

Note: Most articles will quote this result for convex polyhedrons only, but it holds for those concave polyhedra without holes also.

NUMBERS AND THE UNIVERSE.

NUMBERS AND THE UNIVERSE.

Here is a great reference for the number of stars in our galaxy ($\ge 100$ billion stars) and the number of galaxies in the observable Universe ($\ge 100$ billion galaxies) and my favourite,, dark energy and dark matter makes up $95\%$ of the Universe. The rest is only $ 5\%$, that is the observable universe, all the stars, planets,... constitute only $5\%$ of the Universe! Well, that's according to the latest in science at NASA..

http://nasa.tumblr.com/post/136762377389/7-facts-that-will-make-you-feel-very-small

Bit of Fun. Patterns in multiplications.

Bit of Fun. Patterns in multiplications.
I saw this online somewhere. Instead oif $8$ you could put another single digit number but most give boring results. Except $9$ which gives an impressive regular pattern, see below.

$\Large 1\times 9+1=10$

$\Large 12\times 9+2=110$

$\Large 123\times 9+3=1110$

$\Large 1234\times 9+4=11110$

$\Large 12345\times 9+5=111110$

$\Large 123456\times 9+6=1111110$

$\Large 1234567\times 9+7=11111110$

$\Large 12345678\times 9+8=111111110$

$\Large123456789\times 9+9=1111111110$

x