521505020 has 12 divisors (see below), whose sum is σ = 1095160584. Its totient is φ = 208602000.

The previous prime is 521505007. The next prime is 521505031. The reversal of 521505020 is 20505125.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 26075251 = 521505020 / (5 + 2 + 1 + 5 + 0 + 5 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 521504983 and 521505001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13037606 + ... + 13037645.

It is an arithmetic number, because the mean of its divisors is an integer number (91263382).

Almost surely, 2^521505020 is an apocalyptic number.

It is an amenable number.

521505020 is an abundant number, since it is smaller than the sum of its proper divisors (573655564).

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

521505020 is a wasteful number, since it uses less digits than its factorization.

521505020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26075260 (or 26075258 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 20.

The square root of 521505020 is about 22836.4844054421. The cubic root of 521505020 is about 804.9202086468.

The spelling of 521505020 in words is "five hundred twenty-one million, five hundred five thousand, twenty".