# 2018

To celebrate the new year, many posts have been written to share the properties of number $2018$ . And its been pointed out that since its a semi-prime number (a natural number that is product of two prime numbers) its somewhat less interesting.

But still there are lots of beautiful properties and in this blog post I am compiling some properties related to the number 2018 which I found interesting.

-2) In the blog Math with Bad Drawings, Ben Orlin have written about the special days in this year, like the golden ratio day 1-6-18. And we can celebrate it on 6th January or 1st June.

Golden ratio Φ can be approximately written as $1.618...$

And what I found most interesting was a comment on this blog post by michael tamblyn. He points towards the date 2-7-18 which is actually the exponential number ‘e’.

e can approximately be written as $2.718...$

So we can celebrate e-day on 2nd July or on 7th February.

[Both of these dates for phi day and e day are not official but e day is celebrated every year on 2nd July or 7th February]

-1) In the blog Life Through A Mathematician’s Eyes authored by Ioana, she has shared another interesting property. If you write the number 2018 in reverse i.e. 8102 it can be written as the multiplication of 2 prime numbers just like 2018.

$2018 = 2\times1009$

$8102 = 2\times4051$

0) Allex Bellos in the gaurdian posted an awesome puzzle which is to turn the numbers written below into an equation using any one of the operations ÷,+,-,×. And the numbers must be written in the countdown sequence.

${1 0 9 8 7 6 5 4 3 2 1 = 2018}$

Same puzzle can be solved with some different rules e.g. forget about the sequence and use any number you want.

1) In the blog Learn Fun Facts Edmark M. Law has shared this really amazing equation.

2) I tried to find prime numbers using the digits 2, 0, 1, 8

$2+0+1+8 = 11$ (prime number)

$2{^2} + 2{^0} + 2{^1} + 2{^8} = 263$ (prime number)