16442663522121 has 6 divisors (see below), whose sum is σ = 23750513976410. Its totient is φ = 10961775681408.

The previous prime is 16442663522027. The next prime is 16442663522167. The reversal of 16442663522121 is 12122536624461.

It is a happy number.

16442663522121 is a `hidden beast` number, since 1 + 6 + 4 + 4 + 2 + 6 + 635 + 2 + 2 + 1 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15821977959225 + 620685562896 = 3977685^2 + 787836^2 .

It is not a de Polignac number, because 16442663522121 - 2³⁹ = 15892907708233 is a prime.

It is a super-3 number, since 3×16442663522121³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16442663522821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 913481306776 + ... + 913481306793.

Almost surely, 2^{16442663522121} is an apocalyptic number.

It is an amenable number.

16442663522121 is a deficient number, since it is larger than the sum of its proper divisors (7307850454289).

16442663522121 is a wasteful number, since it uses less digits than its factorization.

16442663522121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1826962613575 (or 1826962613572 counting only the distinct ones).

The product of its digits is 829440, while the sum is 45.

The spelling of 16442663522121 in words is "sixteen trillion, four hundred forty-two billion, six hundred sixty-three million, five hundred twenty-two thousand, one hundred twenty-one".