681395528 has 36 divisors (see below), whose sum is σ = 1405998195. Its totient is φ = 309356080.

The previous prime is 681395509. The next prime is 681395557. The reversal of 681395528 is 825593186.

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 only one way, i.e., 340697764 + 340697764 = 18458^2 + 18458^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=18458.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 811733 + ... + 812571.

Almost surely, 2^681395528 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 681395528

681395528 is an abundant number, since it is smaller than the sum of its proper divisors (724602667).

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

681395528 is an equidigital number, since it uses as much as digits as its factorization.

681395528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1706 (or 852 counting only the distinct ones).

The product of its digits is 518400, while the sum is 47.

The square root of 681395528 is about 26103.5539342826. The cubic root of 681395528 is about 879.9670821020.

The spelling of 681395528 in words is "six hundred eighty-one million, three hundred ninety-five thousand, five hundred twenty-eight".