686740586551 has 4 divisors (see below), whose sum is σ = 687182790672. Its totient is φ = 686298382432.

The previous prime is 686740586503. The next prime is 686740586569. The reversal of 686740586551 is 155685047686.

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

It is a cyclic number.

It is not a de Polignac number, because 686740586551 - 2¹¹ = 686740584503 is a prime.

It is a super-2 number, since 2×686740586551² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 686740586551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686740586351) 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, 221099731 + ... + 221102836.

It is an arithmetic number, because the mean of its divisors is an integer number (171795697668).

Almost surely, 2^686740586551 is an apocalyptic number.

686740586551 is a deficient number, since it is larger than the sum of its proper divisors (442204121).

686740586551 is a wasteful number, since it uses less digits than its factorization.

686740586551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 442204120.

The product of its (nonzero) digits is 48384000, while the sum is 61.

The spelling of 686740586551 in words is "six hundred eighty-six billion, seven hundred forty million, five hundred eighty-six thousand, five hundred fifty-one".