521604428 has 6 divisors (see below), whose sum is σ = 912807756. Its totient is φ = 260802212.

The previous prime is 521604409. The next prime is 521604437. The reversal of 521604428 is 824406125.

It is a junction number, because it is equal to n+sod(n) for n = 521604394 and 521604403.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65200550 + ... + 65200557.

It is an arithmetic number, because the mean of its divisors is an integer number (152134626).

Almost surely, 2^521604428 is an apocalyptic number.

It is an amenable number.

521604428 is a deficient number, since it is larger than the sum of its proper divisors (391203328).

521604428 is a wasteful number, since it uses less digits than its factorization.

521604428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130401111 (or 130401109 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 32.

The square root of 521604428 is about 22838.6608188834. The cubic root of 521604428 is about 804.9713493655.

The spelling of 521604428 in words is "five hundred twenty-one million, six hundred four thousand, four hundred twenty-eight".