686558711477 has 4 divisors (see below), whose sum is σ = 686574523116. Its totient is φ = 686542899840.

The previous prime is 686558711471. The next prime is 686558711519. The reversal of 686558711477 is 774117855686.

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 155243092081 + 531315619396 = 394009^2 + 728914^2 .

It is a cyclic number.

It is not a de Polignac number, because 686558711477 - 2²⁴ = 686541934261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686558711471) 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, 7840508 + ... + 7927589.

It is an arithmetic number, because the mean of its divisors is an integer number (171643630779).

Almost surely, 2^686558711477 is an apocalyptic number.

It is an amenable number.

686558711477 is a deficient number, since it is larger than the sum of its proper divisors (15811639).

686558711477 is a wasteful number, since it uses less digits than its factorization.

686558711477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15811638.

The product of its digits is 79027200, while the sum is 65.

The spelling of 686558711477 in words is "six hundred eighty-six billion, five hundred fifty-eight million, seven hundred eleven thousand, four hundred seventy-seven".