91956510865 has 4 divisors (see below), whose sum is σ = 110347813044. Its totient is φ = 73565208688.

The previous prime is 91956510817. The next prime is 91956510869. The reversal of 91956510865 is 56801565919.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11349919296 + 80606591569 = 106536^2 + 283913^2 .

It is a cyclic number.

It is not a de Polignac number, because 91956510865 - 2⁹ = 91956510353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91956510869) 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, 9195651082 + ... + 9195651091.

It is an arithmetic number, because the mean of its divisors is an integer number (27586953261).

Almost surely, 2^91956510865 is an apocalyptic number.

It is an amenable number.

91956510865 is a deficient number, since it is larger than the sum of its proper divisors (18391302179).

91956510865 is a wasteful number, since it uses less digits than its factorization.

91956510865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18391302178.

The product of its (nonzero) digits is 2916000, while the sum is 55.

The spelling of 91956510865 in words is "ninety-one billion, nine hundred fifty-six million, five hundred ten thousand, eight hundred sixty-five".