321211920 has 80 divisors (see below), whose sum is σ = 1001453760. Its totient is φ = 85166592.

The previous prime is 321211901. The next prime is 321211927. The reversal of 321211920 is 29112123.

321211920 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (321211927) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 39222 + ... + 46698.

It is an arithmetic number, because the mean of its divisors is an integer number (12518172).

Almost surely, 2^321211920 is an apocalyptic number.

321211920 is a gapful number since it is divisible by the number (30) 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 321211920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (500726880).

321211920 is an abundant number, since it is smaller than the sum of its proper divisors (680241840).

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

321211920 is a wasteful number, since it uses less digits than its factorization.

321211920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7672 (or 7666 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 321211920 is about 17922.3860018693. The cubic root of 321211920 is about 684.8527717397.

The spelling of 321211920 in words is "three hundred twenty-one million, two hundred eleven thousand, nine hundred twenty".