686206840 has 64 divisors (see below), whose sum is σ = 1757583360. Its totient is φ = 238677120.

The previous prime is 686206813. The next prime is 686206861. The reversal of 686206840 is 48602686.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 686206793 and 686206802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23784 + ... + 44023.

It is an arithmetic number, because the mean of its divisors is an integer number (27462240).

Almost surely, 2^686206840 is an apocalyptic number.

It is an amenable number.

686206840 is an abundant number, since it is smaller than the sum of its proper divisors (1071376520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686206840 is a wasteful number, since it uses less digits than its factorization.

686206840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67852 (or 67848 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 686206840 is about 26195.5500037697. The cubic root of 686206840 is about 882.0333661789.

686206840 divided by its sum of digits (40) gives a palindrome (17155171).

The spelling of 686206840 in words is "six hundred eighty-six million, two hundred six thousand, eight hundred forty".