686344834561 has 4 divisors (see below), whose sum is σ = 686376685872. Its totient is φ = 686312983252.

The previous prime is 686344834547. The next prime is 686344834579. The reversal of 686344834561 is 165438443686.

686344834561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 686344834561 - 2¹⁹ = 686344310273 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 686344834496 and 686344834505.

It is not an unprimeable number, because it can be changed into a prime (686344834501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15893311 + ... + 15936436.

It is an arithmetic number, because the mean of its divisors is an integer number (171594171468).

Almost surely, 2^686344834561 is an apocalyptic number.

It is an amenable number.

686344834561 is a deficient number, since it is larger than the sum of its proper divisors (31851311).

686344834561 is a wasteful number, since it uses less digits than its factorization.

686344834561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31851310.

The product of its digits is 39813120, while the sum is 58.

The spelling of 686344834561 in words is "six hundred eighty-six billion, three hundred forty-four million, eight hundred thirty-four thousand, five hundred sixty-one".