91022021211 has 16 divisors (see below), whose sum is σ = 132405465600. Its totient is φ = 55160778720.

The previous prime is 91022021183. The next prime is 91022021221. The reversal of 91022021211 is 11212022019.

It is not a de Polignac number, because 91022021211 - 2¹¹ = 91022019163 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91022021221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 385326 + ... + 574908.

It is an arithmetic number, because the mean of its divisors is an integer number (8275341600).

Almost surely, 2^91022021211 is an apocalyptic number.

91022021211 is a deficient number, since it is larger than the sum of its proper divisors (41383444389).

91022021211 is a wasteful number, since it uses less digits than its factorization.

91022021211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204146.

The product of its (nonzero) digits is 144, while the sum is 21.

The spelling of 91022021211 in words is "ninety-one billion, twenty-two million, twenty-one thousand, two hundred eleven".