686861831040 has 1024 divisors, whose sum is σ = 2934027878400. Its totient is φ = 132291624960.

The previous prime is 686861831039. The next prime is 686861831059. The reversal of 686861831040 is 40138168686.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 168387721 + ... + 168391799.

It is an arithmetic number, because the mean of its divisors is an integer number (2865261600).

Almost surely, 2^686861831040 is an apocalyptic number.

686861831040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686861831040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1467013939200).

686861831040 is an abundant number, since it is smaller than the sum of its proper divisors (2247166047360).

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

686861831040 is a wasteful number, since it uses less digits than its factorization.

686861831040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4203 (or 4191 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 51.

The spelling of 686861831040 in words is "six hundred eighty-six billion, eight hundred sixty-one million, eight hundred thirty-one thousand, forty".