521291 has 4 divisors (see below), whose sum is σ = 522792. Its totient is φ = 519792.

The previous prime is 521281. The next prime is 521299. The reversal of 521291 is 192125.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521291 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 521291.

It is not an unprimeable number, because it can be changed into a prime (521299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71 + ... + 1023.

It is an arithmetic number, because the mean of its divisors is an integer number (130698).

2⁵²¹²⁹¹ is an apocalyptic number.

521291 is a deficient number, since it is larger than the sum of its proper divisors (1501).

521291 is an equidigital number, since it uses as much as digits as its factorization.

521291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500.

The product of its digits is 180, while the sum is 20.

The square root of 521291 is about 722.0048476292. The cubic root of 521291 is about 80.4810083408.

The spelling of 521291 in words is "five hundred twenty-one thousand, two hundred ninety-one".