681401440 has 48 divisors (see below), whose sum is σ = 1616031648. Its totient is φ = 271507456.

The previous prime is 681401431. The next prime is 681401459. The reversal of 681401440 is 44104186.

It is a junction number, because it is equal to n+sod(n) for n = 681401399 and 681401408.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33984 + ... + 50176.

It is an arithmetic number, because the mean of its divisors is an integer number (33667326).

Almost surely, 2^681401440 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 681401440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (808015824).

681401440 is an abundant number, since it is smaller than the sum of its proper divisors (934630208).

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

681401440 is a wasteful number, since it uses less digits than its factorization.

681401440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16471 (or 16463 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 681401440 is about 26103.6671753223. The cubic root of 681401440 is about 879.9696270509.

The spelling of 681401440 in words is "six hundred eighty-one million, four hundred one thousand, four hundred forty".