321405904 has 10 divisors (see below), whose sum is σ = 622723970. Its totient is φ = 160702944.

The previous prime is 321405899. The next prime is 321405913. The reversal of 321405904 is 409504123.

It can be written as a sum of positive squares in only one way, i.e., 288320400 + 33085504 = 16980^2 + 5752^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10043919 + ... + 10043950.

It is an arithmetic number, because the mean of its divisors is an integer number (62272397).

Almost surely, 2^321405904 is an apocalyptic number.

It is an amenable number.

321405904 is a deficient number, since it is larger than the sum of its proper divisors (301318066).

321405904 is a wasteful number, since it uses less digits than its factorization.

321405904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20087877 (or 20087871 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 321405904 is about 17927.7969644906. The cubic root of 321405904 is about 684.9906077885.

The spelling of 321405904 in words is "three hundred twenty-one million, four hundred five thousand, nine hundred four".