20130311209 has 4 divisors (see below), whose sum is σ = 20241528580. Its totient is φ = 20019093840.

The previous prime is 20130311207. The next prime is 20130311219. The reversal of 20130311209 is 90211303102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10851805584 + 9278505625 = 104172^2 + 96325^2 .

It is a cyclic number.

It is not a de Polignac number, because 20130311209 - 2¹ = 20130311207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20130311209.

It is not an unprimeable number, because it can be changed into a prime (20130311207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55608414 + ... + 55608775.

It is an arithmetic number, because the mean of its divisors is an integer number (5060382145).

Almost surely, 2^20130311209 is an apocalyptic number.

It is an amenable number.

20130311209 is a deficient number, since it is larger than the sum of its proper divisors (111217371).

20130311209 is a wasteful number, since it uses less digits than its factorization.

20130311209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111217370.

The product of its (nonzero) digits is 324, while the sum is 22.

The spelling of 20130311209 in words is "twenty billion, one hundred thirty million, three hundred eleven thousand, two hundred nine".