991222210211211 has 48 divisors (see below), whose sum is σ = 1601513587634688. Its totient is φ = 585616548840000.

The previous prime is 991222210211209. The next prime is 991222210211227. The reversal of 991222210211211 is 112112012222199.

It is a happy number.

991222210211211 is a `hidden beast` number, since 9 + 9 + 1 + 2 + 2 + 221 + 0 + 211 + 211 = 666.

It is not a de Polignac number, because 991222210211211 - 2¹ = 991222210211209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (991222210211231) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 423191916 + ... + 425527721.

It is an arithmetic number, because the mean of its divisors is an integer number (33364866409056).

Almost surely, 2^{991222210211211} is an apocalyptic number.

991222210211211 is a deficient number, since it is larger than the sum of its proper divisors (610291377423477).

991222210211211 is a wasteful number, since it uses less digits than its factorization.

991222210211211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848719952 (or 848719949 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The spelling of 991222210211211 in words is "nine hundred ninety-one trillion, two hundred twenty-two billion, two hundred ten million, two hundred eleven thousand, two hundred eleven".