16809261872 has 60 divisors (see below), whose sum is σ = 35382501000. Its totient is φ = 7732468224.

The previous prime is 16809261817. The next prime is 16809261901. The reversal of 16809261872 is 27816290861.

It is a self number, because there is not a number n which added to its sum of digits gives 16809261872.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 820004 + ... + 840252.

It is an arithmetic number, because the mean of its divisors is an integer number (589708350).

Almost surely, 2^16809261872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16809261872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17691250500).

16809261872 is an abundant number, since it is smaller than the sum of its proper divisors (18573239128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16809261872 is a wasteful number, since it uses less digits than its factorization.

16809261872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20590 (or 20571 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 50.

The spelling of 16809261872 in words is "sixteen billion, eight hundred nine million, two hundred sixty-one thousand, eight hundred seventy-two".