521657472 has 64 divisors (see below), whose sum is σ = 1583611200. Its totient is φ = 149044224.

The previous prime is 521657401. The next prime is 521657501. The reversal of 521657472 is 274756125.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 521657472.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94347 + ... + 99722.

It is an arithmetic number, because the mean of its divisors is an integer number (24743925).

Almost surely, 2^521657472 is an apocalyptic number.

It is an amenable number.

521657472 is an abundant number, since it is smaller than the sum of its proper divisors (1061953728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

521657472 is a wasteful number, since it uses less digits than its factorization.

521657472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194093 (or 194081 counting only the distinct ones).

The product of its digits is 117600, while the sum is 39.

The square root of 521657472 is about 22839.8220658568. The cubic root of 521657472 is about 804.9986353384.

The spelling of 521657472 in words is "five hundred twenty-one million, six hundred fifty-seven thousand, four hundred seventy-two".