4043928221 has 4 divisors (see below), whose sum is σ = 4099324572. Its totient is φ = 3988531872.

The previous prime is 4043928197. The next prime is 4043928233. The reversal of 4043928221 is 1228293404.

4043928221 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 3115202596 + 928725625 = 55814^2 + 30475^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4043928221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4043928271) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27698066 + ... + 27698211.

It is an arithmetic number, because the mean of its divisors is an integer number (1024831143).

Almost surely, 2^4043928221 is an apocalyptic number.

It is an amenable number.

4043928221 is a deficient number, since it is larger than the sum of its proper divisors (55396351).

4043928221 is an equidigital number, since it uses as much as digits as its factorization.

4043928221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55396350.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 4043928221 is about 63591.8880125445. Note that the first 3 decimals coincide. The cubic root of 4043928221 is about 1593.1908840114.

The spelling of 4043928221 in words is "four billion, forty-three million, nine hundred twenty-eight thousand, two hundred twenty-one".