521040128 has 108 divisors (see below), whose sum is σ = 1228576860. Its totient is φ = 219856896.

The previous prime is 521040119. The next prime is 521040131. The reversal of 521040128 is 821040125.

It can be written as a sum of positive squares in 2 ways, for example, as 183656704 + 337383424 = 13552^2 + 18368^2 .

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, 915428 + ... + 915996.

Almost surely, 2^521040128 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 521040128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (614288430).

521040128 is an abundant number, since it is smaller than the sum of its proper divisors (707536732).

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

521040128 is an equidigital number, since it uses as much as digits as its factorization.

521040128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 672 (or 651 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 521040128 is about 22826.3034239011. The cubic root of 521040128 is about 804.6809573777.

The spelling of 521040128 in words is "five hundred twenty-one million, forty thousand, one hundred twenty-eight".