Method names of long numbers used to denote extent of ten (the number of zeros after the unit). There is a long and short system names numbers. In Europe, mostly use the long system names.
Used short system, but a billion called a billion.
 |
ten |
 |
STO |
 |
a thousand |
 |
million |
 |
billion |
 |
billion |
 |
Billiards |
 |
trillion (quintillion) |
 |
sextillion |
 |
septillion |
Mersenne primes
Prime numbers Fermat
Known Farm: 
Simple numbers-twins
Factoral simple
2, 3, 5, 7, 23, 719, 5 039, 39 916 801, 479 001 599, 87 178 291 199.