321374521728 has 768 divisors, whose sum is σ = 1107156960000. Its totient is φ = 91962335232.

The previous prime is 321374521717. The next prime is 321374521771. The reversal of 321374521728 is 827125473123.

321374521728 is a `hidden beast` number, since 3 + 21 + 3 + 7 + 452 + 172 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 453278238 + ... + 453278946.

It is an arithmetic number, because the mean of its divisors is an integer number (1441610625).

Almost surely, 2^321374521728 is an apocalyptic number.

321374521728 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321374521728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (553578480000).

321374521728 is an abundant number, since it is smaller than the sum of its proper divisors (785782438272).

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

321374521728 is a wasteful number, since it uses less digits than its factorization.

321374521728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829 (or 805 counting only the distinct ones).

The product of its digits is 564480, while the sum is 45.

The spelling of 321374521728 in words is "three hundred twenty-one billion, three hundred seventy-four million, five hundred twenty-one thousand, seven hundred twenty-eight".