321721429376 has 32 divisors (see below), whose sum is σ = 645230988000. Its totient is φ = 159781103104.

The previous prime is 321721429363. The next prime is 321721429427. The reversal of 321721429376 is 673924127123.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 321721429376.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8415320 + ... + 8453463.

It is an arithmetic number, because the mean of its divisors is an integer number (20163468375).

Almost surely, 2^321721429376 is an apocalyptic number.

It is an amenable number.

321721429376 is an abundant number, since it is smaller than the sum of its proper divisors (323509558624).

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

321721429376 is a wasteful number, since it uses less digits than its factorization.

321721429376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16868946 (or 16868934 counting only the distinct ones).

The product of its digits is 762048, while the sum is 47.

The spelling of 321721429376 in words is "three hundred twenty-one billion, seven hundred twenty-one million, four hundred twenty-nine thousand, three hundred seventy-six".