521441689 has 4 divisors (see below), whose sum is σ = 526604580. Its totient is φ = 516278800.

The previous prime is 521441647. The next prime is 521441737. The reversal of 521441689 is 986144125.

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

It can be written as a sum of positive squares in 2 ways, for example, as 216590089 + 304851600 = 14717^2 + 17460^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521441689 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521421689) 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, 2581294 + ... + 2581495.

It is an arithmetic number, because the mean of its divisors is an integer number (131651145).

Almost surely, 2^521441689 is an apocalyptic number.

It is an amenable number.

521441689 is a deficient number, since it is larger than the sum of its proper divisors (5162891).

521441689 is a wasteful number, since it uses less digits than its factorization.

521441689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5162890.

The product of its digits is 69120, while the sum is 40.

The square root of 521441689 is about 22835.0977444810. The cubic root of 521441689 is about 804.8876244508.

The spelling of 521441689 in words is "five hundred twenty-one million, four hundred forty-one thousand, six hundred eighty-nine".