4389021 has 48 divisors (see below), whose sum is σ = 8176896. Its totient is φ = 2204928.

The previous prime is 4389017. The next prime is 4389023. The reversal of 4389021 is 1209834.

4389021 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 4389021 - 2² = 4389017 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4389023) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18721 + ... + 18953.

It is an arithmetic number, because the mean of its divisors is an integer number (170352).

Almost surely, 2^4389021 is an apocalyptic number.

It is an amenable number.

4389021 is a deficient number, since it is larger than the sum of its proper divisors (3787875).

4389021 is a wasteful number, since it uses less digits than its factorization.

4389021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 279 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 4389021 is about 2094.9990453458. Note that the first 3 decimals coincide. The cubic root of 4389021 is about 163.7278477502.

The spelling of 4389021 in words is "four million, three hundred eighty-nine thousand, twenty-one".