16809939 has 6 divisors (see below), whose sum is σ = 24281036. Its totient is φ = 11206620.

The previous prime is 16809931. The next prime is 16809943. The reversal of 16809939 is 93990861.

It is not a de Polignac number, because 16809939 - 2³ = 16809931 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16809894 and 16809903.

It is not an unprimeable number, because it can be changed into a prime (16809931) 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 5 ways as a sum of consecutive naturals, for example, 933877 + ... + 933894.

Almost surely, 2^16809939 is an apocalyptic number.

16809939 is a deficient number, since it is larger than the sum of its proper divisors (7471097).

16809939 is a wasteful number, since it uses less digits than its factorization.

16809939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1867777 (or 1867774 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 16809939 is about 4099.9925609689. The cubic root of 16809939 is about 256.1663296928.

The spelling of 16809939 in words is "sixteen million, eight hundred nine thousand, nine hundred thirty-nine".