681581376 has 504 divisors, whose sum is σ = 2529596160. Its totient is φ = 174182400.

The previous prime is 681581359. The next prime is 681581389. The reversal of 681581376 is 673185186.

681581376 is a `hidden beast` number, since 68 + 1 + 581 + 3 + 7 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (504).

It is a super-2 number, since 2×681581376² = 929106344220106752, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 16623916 + ... + 16623956.

It is an arithmetic number, because the mean of its divisors is an integer number (5019040).

Almost surely, 2^681581376 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 681581376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1264798080).

681581376 is an abundant number, since it is smaller than the sum of its proper divisors (1848014784).

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

681581376 is a wasteful number, since it uses less digits than its factorization.

681581376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123 (or 103 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 681581376 is about 26107.1135133703. The cubic root of 681581376 is about 880.0470773713.

The spelling of 681581376 in words is "six hundred eighty-one million, five hundred eighty-one thousand, three hundred seventy-six".