521434221 has 16 divisors (see below), whose sum is σ = 866800128. Its totient is φ = 270874800.

The previous prime is 521434189. The next prime is 521434237. The reversal of 521434221 is 122434125.

It is not a de Polignac number, because 521434221 - 2⁵ = 521434189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 521434191 and 521434200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521434241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1128415 + ... + 1128876.

It is an arithmetic number, because the mean of its divisors is an integer number (54175008).

Almost surely, 2^521434221 is an apocalyptic number.

It is an amenable number.

521434221 is a deficient number, since it is larger than the sum of its proper divisors (345365907).

521434221 is a wasteful number, since it uses less digits than its factorization.

521434221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2257312.

The product of its digits is 1920, while the sum is 24.

The square root of 521434221 is about 22834.9342236846. The cubic root of 521434221 is about 804.8837819441.

Adding to 521434221 its reverse (122434125), we get a palindrome (643868346).

The spelling of 521434221 in words is "five hundred twenty-one million, four hundred thirty-four thousand, two hundred twenty-one".