91086566661 has 64 divisors (see below), whose sum is σ = 149577891840. Its totient is φ = 54489726720.

The previous prime is 91086566647. The next prime is 91086566689. The reversal of 91086566661 is 16666568019.

It is not a de Polignac number, because 91086566661 - 2⁷ = 91086566533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91086566598 and 91086566607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91086066661) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3269356 + ... + 3297098.

It is an arithmetic number, because the mean of its divisors is an integer number (2337154560).

Almost surely, 2^91086566661 is an apocalyptic number.

It is an amenable number.

91086566661 is a deficient number, since it is larger than the sum of its proper divisors (58491325179).

91086566661 is a wasteful number, since it uses less digits than its factorization.

91086566661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28103 (or 28097 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 91086566661 in words is "ninety-one billion, eighty-six million, five hundred sixty-six thousand, six hundred sixty-one".