681857280 has 432 divisors, whose sum is σ = 2644976880. Its totient is φ = 161021952.

The previous prime is 681857279. The next prime is 681857299. The reversal of 681857280 is 82758186.

681857280 is a `hidden beast` number, since 68 + 18 + 572 + 8 + 0 = 666.

681857280 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 84934656 + 596922624 = 9216^2 + 24432^2 .

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 47 ways as a sum of consecutive naturals, for example, 4342962 + ... + 4343118.

Almost surely, 2^681857280 is an apocalyptic number.

681857280 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 681857280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1322488440).

681857280 is an abundant number, since it is smaller than the sum of its proper divisors (1963119600).

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

681857280 is a wasteful number, since it uses less digits than its factorization.

681857280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 45.

The square root of 681857280 is about 26112.3970558047. The cubic root of 681857280 is about 880.1658089768.

The spelling of 681857280 in words is "six hundred eighty-one million, eight hundred fifty-seven thousand, two hundred eighty".