3928321 has 4 divisors (see below), whose sum is σ = 3932500. Its totient is φ = 3924144.

The previous prime is 3928319. The next prime is 3928361. The reversal of 3928321 is 1238293.

3928321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1238293 = 7 ⋅176899.

It can be written as a sum of positive squares in 2 ways, for example, as 360000 + 3568321 = 600^2 + 1889^2 .

It is a cyclic number.

It is not a de Polignac number, because 3928321 - 2¹ = 3928319 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3928321.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3928361) 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 3 ways as a sum of consecutive naturals, for example, 55 + ... + 2803.

It is an arithmetic number, because the mean of its divisors is an integer number (983125).

Almost surely, 2^3928321 is an apocalyptic number.

It is an amenable number.

3928321 is a deficient number, since it is larger than the sum of its proper divisors (4179).

3928321 is a wasteful number, since it uses less digits than its factorization.

3928321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4178.

The product of its digits is 2592, while the sum is 28.

The square root of 3928321 is about 1981.9992431886. Note that the first 3 decimals coincide. The cubic root of 3928321 is about 157.7861899936.

Subtracting from 3928321 its sum of digits (28), we obtain a palindrome (3928293).

It can be divided in two parts, 39283 and 21, that added together give a cube (39304 = 34³).

The spelling of 3928321 in words is "three million, nine hundred twenty-eight thousand, three hundred twenty-one".