91585522161 has 27 divisors (see below), whose sum is σ = 153899277753. Its totient is φ = 52330952520.

The previous prime is 91585522151. The next prime is 91585522277. The reversal of 91585522161 is 16122558519.

The square root of 91585522161 is 302631.

It is a perfect power (a square), and thus also a powerful number.

91585522161 is a `hidden beast` number, since 9 + 1 + 585 + 5 + 2 + 2 + 1 + 61 = 666.

It is not a de Polignac number, because 91585522161 - 2¹³ = 91585513969 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91585522121) 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 26 ways as a sum of consecutive naturals, for example, 6348046 + ... + 6362456.

Almost surely, 2^91585522161 is an apocalyptic number.

91585522161 is the 302631-st square number.

91585522161 is the 151316-th centered octagonal number.

It is an amenable number.

91585522161 is a deficient number, since it is larger than the sum of its proper divisors (62313755592).

91585522161 is an frugal number, since it uses more digits than its factorization.

91585522161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28842 (or 14421 counting only the distinct ones).

The product of its digits is 216000, while the sum is 45.

The spelling of 91585522161 in words is "ninety-one billion, five hundred eighty-five million, five hundred twenty-two thousand, one hundred sixty-one".