91121222111 has 4 divisors (see below), whose sum is σ = 91443205512. Its totient is φ = 90799238712.

The previous prime is 91121222107. The next prime is 91121222117. The reversal of 91121222111 is 11122212119.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91121222111 - 2² = 91121222107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91121222117) 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 3 ways as a sum of consecutive naturals, for example, 160991276 + ... + 160991841.

It is an arithmetic number, because the mean of its divisors is an integer number (22860801378).

Almost surely, 2^91121222111 is an apocalyptic number.

91121222111 is a deficient number, since it is larger than the sum of its proper divisors (321983401).

91121222111 is a wasteful number, since it uses less digits than its factorization.

91121222111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321983400.

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

The spelling of 91121222111 in words is "ninety-one billion, one hundred twenty-one million, two hundred twenty-two thousand, one hundred eleven".