521728834128 has 40 divisors (see below), whose sum is σ = 1349372289408. Its totient is φ = 173706669312.

The previous prime is 521728834117. The next prime is 521728834129. The reversal of 521728834128 is 821438827125.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521728834129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6300376 + ... + 6382647.

Almost surely, 2^521728834128 is an apocalyptic number.

It is an amenable number.

521728834128 is an abundant number, since it is smaller than the sum of its proper divisors (827643455280).

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

521728834128 is a wasteful number, since it uses less digits than its factorization.

521728834128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12683891 (or 12683885 counting only the distinct ones).

The product of its digits is 1720320, while the sum is 51.

The spelling of 521728834128 in words is "five hundred twenty-one billion, seven hundred twenty-eight million, eight hundred thirty-four thousand, one hundred twenty-eight".