521289 has 16 divisors (see below), whose sum is σ = 792000. Its totient is φ = 338688.

The previous prime is 521281. The next prime is 521299. The reversal of 521289 is 982125.

It is not a de Polignac number, because 521289 - 2³ = 521281 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 937 + ... + 1385.

It is an arithmetic number, because the mean of its divisors is an integer number (49500).

2⁵²¹²⁸⁹ is an apocalyptic number.

It is an amenable number.

521289 is a deficient number, since it is larger than the sum of its proper divisors (270711).

521289 is a wasteful number, since it uses less digits than its factorization.

521289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501 (or 495 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 521289 is about 722.0034625956. The cubic root of 521289 is about 80.4809054154.

Adding to 521289 its product of digits (1440), we get a square (522729 = 723²).

The spelling of 521289 in words is "five hundred twenty-one thousand, two hundred eighty-nine".