16545663161 has 4 divisors (see below), whose sum is σ = 17116203300. Its totient is φ = 15975123024.

The previous prime is 16545663149. The next prime is 16545663187. The reversal of 16545663161 is 16136654561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16136654561 = 5839 ⋅2763599.

It can be written as a sum of positive squares in 2 ways, for example, as 9945075625 + 6600587536 = 99725^2 + 81244^2 .

It is a cyclic number.

It is not a de Polignac number, because 16545663161 - 2⁶ = 16545663097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16545663361) 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, 285270026 + ... + 285270083.

It is an arithmetic number, because the mean of its divisors is an integer number (4279050825).

Almost surely, 2^16545663161 is an apocalyptic number.

It is an amenable number.

16545663161 is a deficient number, since it is larger than the sum of its proper divisors (570540139).

16545663161 is an equidigital number, since it uses as much as digits as its factorization.

16545663161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570540138.

The product of its digits is 388800, while the sum is 44.

The spelling of 16545663161 in words is "sixteen billion, five hundred forty-five million, six hundred sixty-three thousand, one hundred sixty-one".