681526728 has 48 divisors (see below), whose sum is σ = 1871812800. Its totient is φ = 223974240.

The previous prime is 681526711. The next prime is 681526739. The reversal of 681526728 is 827625186.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61548 + ... + 71771.

It is an arithmetic number, because the mean of its divisors is an integer number (38996100).

Almost surely, 2^681526728 is an apocalyptic number.

It is an amenable number.

681526728 is an abundant number, since it is smaller than the sum of its proper divisors (1190286072).

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

681526728 is a wasteful number, since it uses less digits than its factorization.

681526728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133402 (or 133395 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 681526728 is about 26106.0668810911. The cubic root of 681526728 is about 880.0235565319.

The spelling of 681526728 in words is "six hundred eighty-one million, five hundred twenty-six thousand, seven hundred twenty-eight".