521389 has 12 divisors (see below), whose sum is σ = 595840. Its totient is φ = 455400.

The previous prime is 521377. The next prime is 521393. The reversal of 521389 is 983125.

It is not a de Polignac number, because 521389 - 2⁵ = 521357 is a prime.

It is a Duffinian number.

521389 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521309) 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 11 ways as a sum of consecutive naturals, for example, 3682 + ... + 3820.

2⁵²¹³⁸⁹ is an apocalyptic number.

It is an amenable number.

521389 is a deficient number, since it is larger than the sum of its proper divisors (74451).

521389 is a wasteful number, since it uses less digits than its factorization.

521389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192 (or 181 counting only the distinct ones).

The product of its digits is 2160, while the sum is 28.

The square root of 521389 is about 722.0727110202. The cubic root of 521389 is about 80.4860513620.

It can be divided in two parts, 52 and 1389, that added together give a palindrome (1441).

The spelling of 521389 in words is "five hundred twenty-one thousand, three hundred eighty-nine".