681587280 has 240 divisors, whose sum is σ = 2559211200. Its totient is φ = 161126400.

The previous prime is 681587251. The next prime is 681587317. The reversal of 681587280 is 82785186.

681587280 is a `hidden beast` number, since 68 + 1 + 587 + 2 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×681587280² = 929122440515596800, which contains 22 as substring.

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, 323671 + ... + 325769.

It is an arithmetic number, because the mean of its divisors is an integer number (10663380).

Almost surely, 2^681587280 is an apocalyptic number.

681587280 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 681587280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1279605600).

681587280 is an abundant number, since it is smaller than the sum of its proper divisors (1877623920).

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

681587280 is a wasteful number, since it uses less digits than its factorization.

681587280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2170 (or 2161 counting only the distinct ones).

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

The square root of 681587280 is about 26107.2265857559. The cubic root of 681587280 is about 880.0496184144.

The spelling of 681587280 in words is "six hundred eighty-one million, five hundred eighty-seven thousand, two hundred eighty".