521020 has 24 divisors (see below), whose sum is σ = 1108800. Its totient is φ = 205632.

The previous prime is 521009. The next prime is 521021. The reversal of 521020 is 20125.

521020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 520988 and 521006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2061 + ... + 2299.

It is an arithmetic number, because the mean of its divisors is an integer number (46200).

2⁵²¹⁰²⁰ is an apocalyptic number.

It is an amenable number.

521020 is an abundant number, since it is smaller than the sum of its proper divisors (587780).

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

521020 is a wasteful number, since it uses less digits than its factorization.

521020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357 (or 355 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 10.

The square root of 521020 is about 721.8171513618. The cubic root of 521020 is about 80.4670595523.

Adding to 521020 its reverse (20125), we get a palindrome (541145).

It can be divided in two parts, 5 and 21020, that added together give a square (21025 = 145²).

The spelling of 521020 in words is "five hundred twenty-one thousand, twenty".