12211212209 has 4 divisors (see below), whose sum is σ = 13955671104. Its totient is φ = 10466753316.

The previous prime is 12211212161. The next prime is 12211212257. The reversal of 12211212209 is 90221211221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (12211212161) and next prime (12211212257).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12211212209 is a prime.

It is a super-2 number, since 2×12211212209² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12211212109) 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, 872229437 + ... + 872229450.

It is an arithmetic number, because the mean of its divisors is an integer number (3488917776).

Almost surely, 2^12211212209 is an apocalyptic number.

It is an amenable number.

12211212209 is a deficient number, since it is larger than the sum of its proper divisors (1744458895).

12211212209 is an equidigital number, since it uses as much as digits as its factorization.

12211212209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1744458894.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 12211212209 in words is "twelve billion, two hundred eleven million, two hundred twelve thousand, two hundred nine".