91892815885 has 16 divisors (see below), whose sum is σ = 118785918384. Its totient is φ = 67840952832.

The previous prime is 91892815871. The next prime is 91892815891. The reversal of 91892815885 is 58851829819.

It can be written as a sum of positive squares in 8 ways, for example, as 4654104841 + 87238711044 = 68221^2 + 295362^2 .

It is a cyclic number.

It is not a de Polignac number, because 91892815885 - 2⁵ = 91892815853 is a prime.

It is a super-2 number, since 2×91892815885² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53289 + ... + 432001.

It is an arithmetic number, because the mean of its divisors is an integer number (7424119899).

Almost surely, 2^91892815885 is an apocalyptic number.

It is an amenable number.

91892815885 is a deficient number, since it is larger than the sum of its proper divisors (26893102499).

91892815885 is a wasteful number, since it uses less digits than its factorization.

91892815885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382464.

The product of its digits is 16588800, while the sum is 64.

The spelling of 91892815885 in words is "ninety-one billion, eight hundred ninety-two million, eight hundred fifteen thousand, eight hundred eighty-five".