16809885 has 12 divisors (see below), whose sum is σ = 29137212. Its totient is φ = 8965248.

The previous prime is 16809869. The next prime is 16809887. The reversal of 16809885 is 58890861.

It can be written as a sum of positive squares in 2 ways, for example, as 9696996 + 7112889 = 3114^2 + 2667^2 .

It is not a de Polignac number, because 16809885 - 2⁴ = 16809869 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 373553 = 16809885 / (1 + 6 + 8 + 0 + 9 + 8 + 8 + 5).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16809885.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16809887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 186732 + ... + 186821.

It is an arithmetic number, because the mean of its divisors is an integer number (2428101).

Almost surely, 2^16809885 is an apocalyptic number.

16809885 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16809885 is a deficient number, since it is larger than the sum of its proper divisors (12327327).

16809885 is a wasteful number, since it uses less digits than its factorization.

16809885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373564 (or 373561 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 45.

The square root of 16809885 is about 4099.9859755858. The cubic root of 16809885 is about 256.1660553909.

The spelling of 16809885 in words is "sixteen million, eight hundred nine thousand, eight hundred eighty-five".