16566111101 has 4 divisors (see below), whose sum is σ = 16639089792. Its totient is φ = 16493132412.

The previous prime is 16566111073. The next prime is 16566111113. The reversal of 16566111101 is 10111166561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10111166561 = 331 ⋅30547331.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16566111101 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16566111181) 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, 36489005 + ... + 36489458.

It is an arithmetic number, because the mean of its divisors is an integer number (4159772448).

Almost surely, 2^16566111101 is an apocalyptic number.

It is an amenable number.

16566111101 is a deficient number, since it is larger than the sum of its proper divisors (72978691).

16566111101 is an equidigital number, since it uses as much as digits as its factorization.

16566111101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72978690.

The product of its (nonzero) digits is 1080, while the sum is 29.

Adding to 16566111101 its reverse (10111166561), we get a palindrome (26677277662).

The spelling of 16566111101 in words is "sixteen billion, five hundred sixty-six million, one hundred eleven thousand, one hundred one".