520681 has 4 divisors (see below), whose sum is σ = 595072. Its totient is φ = 446292.

The previous prime is 520679. The next prime is 520691. The reversal of 520681 is 186025.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 520681 - 2¹ = 520679 is a prime.

It is a super-2 number, since 2×520681² = 542217407522, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (520621) 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 3 ways as a sum of consecutive naturals, for example, 37185 + ... + 37198.

It is an arithmetic number, because the mean of its divisors is an integer number (148768).

2⁵²⁰⁶⁸¹ is an apocalyptic number.

It is an amenable number.

520681 is a deficient number, since it is larger than the sum of its proper divisors (74391).

520681 is an equidigital number, since it uses as much as digits as its factorization.

520681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74390.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 520681 is about 721.5822891396. The cubic root of 520681 is about 80.4496038874.

The spelling of 520681 in words is "five hundred twenty thousand, six hundred eighty-one".