520825309 has 4 divisors (see below), whose sum is σ = 520877500. Its totient is φ = 520773120.

The previous prime is 520825307. The next prime is 520825313. The reversal of 520825309 is 903528025.

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 can be written as a sum of positive squares in 2 ways, for example, as 158684409 + 362140900 = 12597^2 + 19030^2 .

It is a cyclic number.

It is not a de Polignac number, because 520825309 - 2¹ = 520825307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520825307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5934 + ... + 32815.

It is an arithmetic number, because the mean of its divisors is an integer number (130219375).

Almost surely, 2^520825309 is an apocalyptic number.

It is an amenable number.

520825309 is a deficient number, since it is larger than the sum of its proper divisors (52191).

520825309 is a wasteful number, since it uses less digits than its factorization.

520825309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52190.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 520825309 is about 22821.5974243697. The cubic root of 520825309 is about 804.5703551989.

The spelling of 520825309 in words is "five hundred twenty million, eight hundred twenty-five thousand, three hundred nine".