321540432 has 80 divisors (see below), whose sum is σ = 861611520. Its totient is φ = 103219200.

The previous prime is 321540421. The next prime is 321540433. The reversal of 321540432 is 234045123.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321540433) 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, 417744 + ... + 418512.

It is an arithmetic number, because the mean of its divisors is an integer number (10770144).

Almost surely, 2^321540432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 321540432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (430805760).

321540432 is an abundant number, since it is smaller than the sum of its proper divisors (540071088).

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

321540432 is a wasteful number, since it uses less digits than its factorization.

321540432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092 (or 1086 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 24.

The square root of 321540432 is about 17931.5485109346. The cubic root of 321540432 is about 685.0861645922.

Adding to 321540432 its reverse (234045123), we get a palindrome (555585555).

The spelling of 321540432 in words is "three hundred twenty-one million, five hundred forty thousand, four hundred thirty-two".