91211011211 has 16 divisors (see below), whose sum is σ = 94840886400. Its totient is φ = 87662227968.

The previous prime is 91211011147. The next prime is 91211011231. The reversal of 91211011211 is 11211011219.

It is a cyclic number.

It is not a de Polignac number, because 91211011211 - 2⁶ = 91211011147 is a prime.

It is a super-2 number, since 2×91211011211² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91211011231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 727655 + ... + 843743.

It is an arithmetic number, because the mean of its divisors is an integer number (5927555400).

Almost surely, 2^91211011211 is an apocalyptic number.

91211011211 is a deficient number, since it is larger than the sum of its proper divisors (3629875189).

91211011211 is a wasteful number, since it uses less digits than its factorization.

91211011211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116438.

The product of its (nonzero) digits is 36, while the sum is 20.

The spelling of 91211011211 in words is "ninety-one billion, two hundred eleven million, eleven thousand, two hundred eleven".