91122112121 has 4 divisors (see below), whose sum is σ = 93060880512. Its totient is φ = 89183343732.

The previous prime is 91122112117. The next prime is 91122112127. The reversal of 91122112121 is 12121122119.

It is a happy number.

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 91122112121 - 2² = 91122112117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91122112127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 969384125 + ... + 969384218.

It is an arithmetic number, because the mean of its divisors is an integer number (23265220128).

Almost surely, 2^91122112121 is an apocalyptic number.

It is an amenable number.

91122112121 is a deficient number, since it is larger than the sum of its proper divisors (1938768391).

91122112121 is a wasteful number, since it uses less digits than its factorization.

91122112121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1938768390.

The product of its digits is 144, while the sum is 23.

The spelling of 91122112121 in words is "ninety-one billion, one hundred twenty-two million, one hundred twelve thousand, one hundred twenty-one".