321320440 has 96 divisors (see below), whose sum is σ = 853221600. Its totient is φ = 108568320.

The previous prime is 321320423. The next prime is 321320453. The reversal of 321320440 is 44023123.

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 23 ways as a sum of consecutive naturals, for example, 138006 + ... + 140314.

It is an arithmetic number, because the mean of its divisors is an integer number (8887725).

Almost surely, 2^321320440 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 321320440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (426610800).

321320440 is an abundant number, since it is smaller than the sum of its proper divisors (531901160).

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

321320440 is a wasteful number, since it uses less digits than its factorization.

321320440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2405 (or 2394 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 321320440 is about 17925.4132448878. The cubic root of 321320440 is about 684.9298878637.

Adding to 321320440 its reverse (44023123), we get a palindrome (365343563).

It can be divided in two parts, 3213 and 20440, that added together give a triangular number (23653 = T₂₁₇).

The spelling of 321320440 in words is "three hundred twenty-one million, three hundred twenty thousand, four hundred forty".