321081840 has 240 divisors, whose sum is σ = 1160238240. Its totient is φ = 81607680.

The previous prime is 321081821. The next prime is 321081847. The reversal of 321081840 is 48180123.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321081847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1142500 + ... + 1142780.

It is an arithmetic number, because the mean of its divisors is an integer number (4834326).

Almost surely, 2^321081840 is an apocalyptic number.

321081840 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 321081840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (580119120).

321081840 is an abundant number, since it is smaller than the sum of its proper divisors (839156400).

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

321081840 is a wasteful number, since it uses less digits than its factorization.

321081840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 321081840 is about 17918.7566532949. The cubic root of 321081840 is about 684.7603118285.

The spelling of 321081840 in words is "three hundred twenty-one million, eighty-one thousand, eight hundred forty".