20123212209 has 16 divisors (see below), whose sum is σ = 26892767232. Its totient is φ = 13384605008.

The previous prime is 20123212183. The next prime is 20123212243. The reversal of 20123212209 is 90221232102.

It is a cyclic number.

It is not a de Polignac number, because 20123212209 - 2⁹ = 20123211697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20123212289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2541034 + ... + 2548940.

It is an arithmetic number, because the mean of its divisors is an integer number (1680797952).

Almost surely, 2^20123212209 is an apocalyptic number.

It is an amenable number.

20123212209 is a deficient number, since it is larger than the sum of its proper divisors (6769555023).

20123212209 is an equidigital number, since it uses as much as digits as its factorization.

20123212209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9756.

The product of its (nonzero) digits is 864, while the sum is 24.

The spelling of 20123212209 in words is "twenty billion, one hundred twenty-three million, two hundred twelve thousand, two hundred nine".