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Guide and features
Guide and features
Science, Technology, Engineering and Mathematics
Featured Early Years Foundation Stage; US Kindergarten
Featured UK Key Stage 1&2; US Grades 1-4
Featured UK Key Stage 3-5; US Grades 5-12
Featured UK Key Stage 1, US Grade 1 & 2
Featured UK Key Stage 2; US Grade 3 & 4
Featured UK Key Stages 3 & 4; US Grade 5-10
Featured UK Key Stage 4 & 5; US Grade 11 & 12
Stage: 3, 4 and 5
Many seemingly boring whole numbers are known to possess some curious property that actually makes them rather interesting. Examples of some interesting properties of numbers are
Why is it interesting?
It is the smallest prime.
A perfect number: it is equal to the sum of its proper factors: $28 = 1+2+4+7+14$.
$100=2^2$ in binary, $100=3^2$ in base $3$, $100=10^2$ in base $10$ and $100=n^2$ in base $n$
The total number of different symmetry structures crystals in three dimensions can exhibit.
The hundredth prime number .
Take any 3 digit number whose digits are not all the same, reverse it and subtract from the first, take the new number and add its reverse. This will equals $1089$.
The smallest number expressible as the sum of two cubes in two different ways.
The smallest prime number such that the sum of its digits is a perfect number.
The largest prime number known in $2008$.
The challenge is this:
What is the most interesting mathematical fact or property of the number 2009 that you can discover?
You are encouraged to use spreadsheets or computers to look for interesting properties or to use the internet to search for connections in science. Be inventive! We would love to see some really creative ideas involving the number $2009$.
As this is an investigative problem, we shall wait until July to publish the best solutions, giving you plenty of time to think about it!
Meet the team
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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Millennium Mathematics Project