Almanac of Interesting Numbers

–1

largest negative integer

0

zero

cardinality of the empty set

the additive identity

was represented using a shell in the ancient Mayan civilisation

1

the multiplicative identity

the only natural number that isn’t prime or composite

wasn’t considered a “number” by many ancient and medieval mathematicians

2

smallest and only even prime number

Euler characteristic of a polyhedron homeomorphic to a sphere

3

number of dimensions we can see

number of particles generations in the standard model

first Mersenne prime

4

smallest composite number

maximum number of colours needed to colour any map in the Euclidean plane

number of Nucleobase types in the DNA: A, G, C, T

unlucky number in Chinese, Japanese and Korean culture