16442023641521 has 4 divisors (see below), whose sum is σ = 16442046345972. Its totient is φ = 16442000937072.

The previous prime is 16442023641487. The next prime is 16442023641529. The reversal of 16442023641521 is 12514632024461.

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 1345690481521 + 15096333160000 = 1160039^2 + 3885400^2 .

It is a cyclic number.

It is not a de Polignac number, because 16442023641521 - 2¹⁸ = 16442023379377 is a prime.

It is a super-3 number, since 3×16442023641521³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16442023641529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10228910 + ... + 11726663.

It is an arithmetic number, because the mean of its divisors is an integer number (4110511586493).

Almost surely, 2^{16442023641521} is an apocalyptic number.

It is an amenable number.

16442023641521 is a deficient number, since it is larger than the sum of its proper divisors (22704451).

16442023641521 is an equidigital number, since it uses as much as digits as its factorization.

16442023641521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22704450.

The product of its (nonzero) digits is 276480, while the sum is 41.

Adding to 16442023641521 its reverse (12514632024461), we get a palindrome (28956655665982).

The spelling of 16442023641521 in words is "sixteen trillion, four hundred forty-two billion, twenty-three million, six hundred forty-one thousand, five hundred twenty-one".