16320444021 has 24 divisors (see below), whose sum is σ = 27282727680. Its totient is φ = 9207914976.

The previous prime is 16320444017. The next prime is 16320444059. The reversal of 16320444021 is 12044402361.

It is a happy number.

16320444021 is a `hidden beast` number, since 1 + 632 + 0 + 4 + 4 + 4 + 0 + 21 = 666.

It is not a de Polignac number, because 16320444021 - 2² = 16320444017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16320444001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1634610 + ... + 1644563.

It is an arithmetic number, because the mean of its divisors is an integer number (1136780320).

Almost surely, 2^16320444021 is an apocalyptic number.

It is an amenable number.

16320444021 is a deficient number, since it is larger than the sum of its proper divisors (10962283659).

16320444021 is a wasteful number, since it uses less digits than its factorization.

16320444021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3279265 (or 3279262 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 16320444021 its reverse (12044402361), we get a palindrome (28364846382).

The spelling of 16320444021 in words is "sixteen billion, three hundred twenty million, four hundred forty-four thousand, twenty-one".