9212211212221 has 4 divisors (see below), whose sum is σ = 9212690859232. Its totient is φ = 9211731565212.

The previous prime is 9212211212143. The next prime is 9212211212231. The reversal of 9212211212221 is 1222121122129.

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 a cyclic number.

It is not a de Polignac number, because 9212211212221 - 2²¹ = 9212209115069 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 9212211212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9212211212231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 239794695 + ... + 239833108.

It is an arithmetic number, because the mean of its divisors is an integer number (2303172714808).

Almost surely, 2^{9212211212221} is an apocalyptic number.

It is an amenable number.

9212211212221 is a deficient number, since it is larger than the sum of its proper divisors (479647011).

9212211212221 is a wasteful number, since it uses less digits than its factorization.

9212211212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479647010.

The product of its digits is 1152, while the sum is 28.

The spelling of 9212211212221 in words is "nine trillion, two hundred twelve billion, two hundred eleven million, two hundred twelve thousand, two hundred twenty-one".