91010000091 has 4 divisors (see below), whose sum is σ = 121346666792. Its totient is φ = 60673333392.

The previous prime is 91010000087. The next prime is 91010000093. The reversal of 91010000091 is 19000001019.

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

It is not a de Polignac number, because 91010000091 - 2² = 91010000087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91010000093) 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 3 ways as a sum of consecutive naturals, for example, 15168333346 + ... + 15168333351.

It is an arithmetic number, because the mean of its divisors is an integer number (30336666698).

Almost surely, 2^91010000091 is an apocalyptic number.

91010000091 is a deficient number, since it is larger than the sum of its proper divisors (30336666701).

91010000091 is a wasteful number, since it uses less digits than its factorization.

91010000091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30336666700.

The product of its (nonzero) digits is 81, while the sum is 21.

The spelling of 91010000091 in words is "ninety-one billion, ten million, ninety-one", and thus it is an aban number and an uban number.