686447876417 has 4 divisors (see below), whose sum is σ = 691458444996. Its totient is φ = 681437307840.

The previous prime is 686447876393. The next prime is 686447876447. The reversal of 686447876417 is 714678744686.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 411168218176 + 275279658241 = 641224^2 + 524671^2 .

It is a cyclic number.

It is not a de Polignac number, because 686447876417 - 2⁶ = 686447876353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686447876447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2505284084 + ... + 2505284357.

It is an arithmetic number, because the mean of its divisors is an integer number (172864611249).

Almost surely, 2^686447876417 is an apocalyptic number.

It is an amenable number.

686447876417 is a deficient number, since it is larger than the sum of its proper divisors (5010568579).

686447876417 is a wasteful number, since it uses less digits than its factorization.

686447876417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5010568578.

The product of its digits is 303464448, while the sum is 68.

The spelling of 686447876417 in words is "six hundred eighty-six billion, four hundred forty-seven million, eight hundred seventy-six thousand, four hundred seventeen".