681859343844 has 192 divisors, whose sum is σ = 2139632947200. Its totient is φ = 183565046016.

The previous prime is 681859343827. The next prime is 681859343857. The reversal of 681859343844 is 448343958186.

681859343844 is a `hidden beast` number, since 6 + 8 + 1 + 8 + 593 + 4 + 38 + 4 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 872352 + ... + 1457640.

It is an arithmetic number, because the mean of its divisors is an integer number (11143921600).

Almost surely, 2^681859343844 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681859343844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1069816473600).

681859343844 is an abundant number, since it is smaller than the sum of its proper divisors (1457773603356).

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

681859343844 is a wasteful number, since it uses less digits than its factorization.

681859343844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 585399 (or 585391 counting only the distinct ones).

The product of its digits is 79626240, while the sum is 63.

The spelling of 681859343844 in words is "six hundred eighty-one billion, eight hundred fifty-nine million, three hundred forty-three thousand, eight hundred forty-four".