520891 has 4 divisors (see below), whose sum is σ = 595312. Its totient is φ = 446472.

The previous prime is 520889. The next prime is 520913. The reversal of 520891 is 198025.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 520891 - 2¹ = 520889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (520841) 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, 37200 + ... + 37213.

It is an arithmetic number, because the mean of its divisors is an integer number (148828).

2⁵²⁰⁸⁹¹ is an apocalyptic number.

520891 is a deficient number, since it is larger than the sum of its proper divisors (74421).

520891 is an equidigital number, since it uses as much as digits as its factorization.

520891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74420.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 520891 is about 721.7277880198. The cubic root of 520891 is about 80.4604180238.

The spelling of 520891 in words is "five hundred twenty thousand, eight hundred ninety-one".