16809261871 has 4 divisors (see below), whose sum is σ = 16809706144. Its totient is φ = 16808817600.

The previous prime is 16809261817. The next prime is 16809261901. The reversal of 16809261871 is 17816290861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17816290861 = 19 ⋅937699519.

It is a cyclic number.

It is not a de Polignac number, because 16809261871 - 2⁷ = 16809261743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16809261571) 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, 159495 + ... + 243016.

It is an arithmetic number, because the mean of its divisors is an integer number (4202426536).

Almost surely, 2^16809261871 is an apocalyptic number.

16809261871 is a deficient number, since it is larger than the sum of its proper divisors (444273).

16809261871 is an equidigital number, since it uses as much as digits as its factorization.

16809261871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444272.

The product of its (nonzero) digits is 290304, while the sum is 49.

The spelling of 16809261871 in words is "sixteen billion, eight hundred nine million, two hundred sixty-one thousand, eight hundred seventy-one".