3728321 has 4 divisors (see below), whose sum is σ = 3947652. Its totient is φ = 3508992.

The previous prime is 3728317. The next prime is 3728357. The reversal of 3728321 is 1238273.

3728321 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.

It can be written as a sum of positive squares in 2 ways, for example, as 3441025 + 287296 = 1855^2 + 536^2 .

It is a cyclic number.

It is not a de Polignac number, because 3728321 - 2² = 3728317 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3728311) 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, 109640 + ... + 109673.

It is an arithmetic number, because the mean of its divisors is an integer number (986913).

Almost surely, 2^3728321 is an apocalyptic number.

It is an amenable number.

3728321 is a deficient number, since it is larger than the sum of its proper divisors (219331).

3728321 is a wasteful number, since it uses less digits than its factorization.

3728321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219330.

The product of its digits is 2016, while the sum is 26.

The square root of 3728321 is about 1930.8860660329. The cubic root of 3728321 is about 155.0616612111.

The spelling of 3728321 in words is "three million, seven hundred twenty-eight thousand, three hundred twenty-one".