686805811 has 16 divisors (see below), whose sum is σ = 726566400. Its totient is φ = 648271008.

The previous prime is 686805809. The next prime is 686805817. The reversal of 686805811 is 118508686.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 686805811 - 2¹ = 686805809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686805817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 268806 + ... + 271348.

It is an arithmetic number, because the mean of its divisors is an integer number (45410400).

Almost surely, 2^686805811 is an apocalyptic number.

686805811 is a deficient number, since it is larger than the sum of its proper divisors (39760589).

686805811 is a wasteful number, since it uses less digits than its factorization.

686805811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2778.

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 686805811 is about 26206.9801961233. The cubic root of 686805811 is about 882.2899257344.

The spelling of 686805811 in words is "six hundred eighty-six million, eight hundred five thousand, eight hundred eleven".