681247872 has 72 divisors (see below), whose sum is σ = 1962914265. Its totient is φ = 226787328.

The previous prime is 681247843. The next prime is 681247873. The reversal of 681247872 is 278742186.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 673091136 + 8156736 = 25944^2 + 2856^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=18456.

It is not an unprimeable number, because it can be changed into a prime (681247873) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 885504 + ... + 886272.

Almost surely, 2^681247872 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 681247872

681247872 is an abundant number, since it is smaller than the sum of its proper divisors (1281666393).

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

681247872 is an frugal number, since it uses more digits than its factorization.

681247872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1558 (or 774 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 681247872 is about 26100.7255071578. The cubic root of 681247872 is about 879.9035155925.

The spelling of 681247872 in words is "six hundred eighty-one million, two hundred forty-seven thousand, eight hundred seventy-two".