16565321376001 has 4 divisors (see below), whose sum is σ = 16636417176132. Its totient is φ = 16494225575872.

The previous prime is 16565321375983. The next prime is 16565321376011. The reversal of 16565321376001 is 10067312356561.

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 4490224570225 + 12075096805776 = 2119015^2 + 3474924^2 .

It is a cyclic number.

It is not a de Polignac number, because 16565321376001 - 2²⁵ = 16565287821569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16565321376011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35547899716 + ... + 35547900181.

It is an arithmetic number, because the mean of its divisors is an integer number (4159104294033).

Almost surely, 2^{16565321376001} is an apocalyptic number.

It is an amenable number.

16565321376001 is a deficient number, since it is larger than the sum of its proper divisors (71095800131).

16565321376001 is an equidigital number, since it uses as much as digits as its factorization.

16565321376001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71095800130.

The product of its (nonzero) digits is 680400, while the sum is 46.

The spelling of 16565321376001 in words is "sixteen trillion, five hundred sixty-five billion, three hundred twenty-one million, three hundred seventy-six thousand, one".