520521789 has 4 divisors (see below), whose sum is σ = 694029056. Its totient is φ = 347014524.

The previous prime is 520521787. The next prime is 520521811. The reversal of 520521789 is 987125025.

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 520521789 - 2¹ = 520521787 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520521787) 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, 86753629 + ... + 86753634.

It is an arithmetic number, because the mean of its divisors is an integer number (173507264).

Almost surely, 2^520521789 is an apocalyptic number.

It is an amenable number.

520521789 is a deficient number, since it is larger than the sum of its proper divisors (173507267).

520521789 is a wasteful number, since it uses less digits than its factorization.

520521789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173507266.

The product of its (nonzero) digits is 50400, while the sum is 39.

The square root of 520521789 is about 22814.9466140072. The cubic root of 520521789 is about 804.4140323761.

The spelling of 520521789 in words is "five hundred twenty million, five hundred twenty-one thousand, seven hundred eighty-nine".