521704 has 8 divisors (see below), whose sum is σ = 978210. Its totient is φ = 260848.

The previous prime is 521693. The next prime is 521707. The reversal of 521704 is 407125.

It can be written as a sum of positive squares in only one way, i.e., 492804 + 28900 = 702^2 + 170^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (19) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (521707) 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 as a sum of consecutive naturals, namely, 32599 + ... + 32614.

2⁵²¹⁷⁰⁴ is an apocalyptic number.

It is an amenable number.

521704 is a deficient number, since it is larger than the sum of its proper divisors (456506).

521704 is a wasteful number, since it uses less digits than its factorization.

521704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65219 (or 65215 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 521704 is about 722.2908001629. The cubic root of 521704 is about 80.5022567941.

Adding to 521704 its reverse (407125), we get a palindrome (928829).

It can be divided in two parts, 521 and 704, that added together give a triangular number (1225 = T₄₉).

The spelling of 521704 in words is "five hundred twenty-one thousand, seven hundred four".