681431808 has 288 divisors, whose sum is σ = 2101559040. Its totient is φ = 194641920.

The previous prime is 681431797. The next prime is 681431813. The reversal of 681431808 is 808134186.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10170591 + ... + 10170657.

It is an arithmetic number, because the mean of its divisors is an integer number (7297080).

Almost surely, 2^681431808 is an apocalyptic number.

681431808 is a gapful number since it is divisible by the number (68) 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 681431808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1050779520).

681431808 is an abundant number, since it is smaller than the sum of its proper divisors (1420127232).

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

681431808 is a wasteful number, since it uses less digits than its factorization.

681431808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 39.

The square root of 681431808 is about 26104.2488495647. The cubic root of 681431808 is about 879.9826993844.

The spelling of 681431808 in words is "six hundred eighty-one million, four hundred thirty-one thousand, eight hundred eight".