681881184 has 144 divisors (see below), whose sum is σ = 2036047104. Its totient is φ = 216057600.

The previous prime is 681881183. The next prime is 681881273. The reversal of 681881184 is 481188186.

It is a tau number, because it is divible by the number of its divisors (144).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681881183) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2059899 + ... + 2060229.

It is an arithmetic number, because the mean of its divisors is an integer number (14139216).

Almost surely, 2^681881184 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 681881184, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1018023552).

681881184 is an abundant number, since it is smaller than the sum of its proper divisors (1354165920).

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

681881184 is a wasteful number, since it uses less digits than its factorization.

681881184 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681 (or 670 counting only the distinct ones).

The product of its digits is 98304, while the sum is 45.

The square root of 681881184 is about 26112.8547654216. The cubic root of 681881184 is about 880.1760942365.

The spelling of 681881184 in words is "six hundred eighty-one million, eight hundred eighty-one thousand, one hundred eighty-four".