866786235086691 has 24 divisors (see below), whose sum is σ = 1285865096802000. Its totient is φ = 562238830984896.

The previous prime is 866786235086663. The next prime is 866786235086713. The reversal of 866786235086691 is 196680532687668.

866786235086691 is a `hidden beast` number, since 8 + 6 + 6 + 7 + 86 + 23 + 508 + 6 + 6 + 9 + 1 = 666.

It is not a de Polignac number, because 866786235086691 - 2³⁵ = 866751875348323 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 866786235086691.

It is not an unprimeable number, because it can be changed into a prime (866786235088691) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 258179685 + ... + 261515433.

It is an arithmetic number, because the mean of its divisors is an integer number (53577712366750).

Almost surely, 2^{866786235086691} is an apocalyptic number.

866786235086691 is a deficient number, since it is larger than the sum of its proper divisors (419078861715309).

866786235086691 is a wasteful number, since it uses less digits than its factorization.

866786235086691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4116115 (or 4116112 counting only the distinct ones).

The product of its (nonzero) digits is 7524679680, while the sum is 81.

The spelling of 866786235086691 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, two hundred thirty-five million, eighty-six thousand, six hundred ninety-one".