91221211101 has 16 divisors (see below), whose sum is σ = 122347425024. Its totient is φ = 60455083584.

The previous prime is 91221211091. The next prime is 91221211153. The reversal of 91221211101 is 10111212219.

It is not a de Polignac number, because 91221211101 - 2¹⁴ = 91221194717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91221211901) 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 15 ways as a sum of consecutive naturals, for example, 653260 + ... + 780506.

It is an arithmetic number, because the mean of its divisors is an integer number (7646714064).

Almost surely, 2^91221211101 is an apocalyptic number.

It is an amenable number.

91221211101 is a deficient number, since it is larger than the sum of its proper divisors (31126213923).

91221211101 is a wasteful number, since it uses less digits than its factorization.

91221211101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128660.

The product of its (nonzero) digits is 72, while the sum is 21.

The spelling of 91221211101 in words is "ninety-one billion, two hundred twenty-one million, two hundred eleven thousand, one hundred one".