16442621504065 has 4 divisors (see below), whose sum is σ = 19731145804884. Its totient is φ = 13154097203248.

The previous prime is 16442621504003. The next prime is 16442621504077. The reversal of 16442621504065 is 56040512624461.

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 10549607936256 + 5893013567809 = 3248016^2 + 2427553^2 .

It is a cyclic number.

It is not a de Polignac number, because 16442621504065 - 2¹⁹ = 16442620979777 is a prime.

It is a super-3 number, since 3×16442621504065³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1644262150402 + ... + 1644262150411.

It is an arithmetic number, because the mean of its divisors is an integer number (4932786451221).

Almost surely, 2^{16442621504065} is an apocalyptic number.

It is an amenable number.

16442621504065 is a deficient number, since it is larger than the sum of its proper divisors (3288524300819).

16442621504065 is an equidigital number, since it uses as much as digits as its factorization.

16442621504065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3288524300818.

The product of its (nonzero) digits is 1382400, while the sum is 46.

The spelling of 16442621504065 in words is "sixteen trillion, four hundred forty-two billion, six hundred twenty-one million, five hundred four thousand, sixty-five".