681557760 has 576 divisors, whose sum is σ = 2740268160. Its totient is φ = 159252480.

The previous prime is 681557743. The next prime is 681557771. The reversal of 681557760 is 67755186.

681557760 is a `hidden beast` number, since 6 + 8 + 15 + 577 + 60 = 666.

681557760 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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, 16623340 + ... + 16623380.

It is an arithmetic number, because the mean of its divisors is an integer number (4757410).

Almost surely, 2^681557760 is an apocalyptic number.

681557760 is a gapful number since it is divisible by the number (60) 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 681557760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1370134080).

681557760 is an abundant number, since it is smaller than the sum of its proper divisors (2058710400).

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

681557760 is a wasteful number, since it uses less digits than its factorization.

681557760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 352800, while the sum is 45.

The square root of 681557760 is about 26106.6612189303. The cubic root of 681557760 is about 880.0369130522.

The spelling of 681557760 in words is "six hundred eighty-one million, five hundred fifty-seven thousand, seven hundred sixty".