16811409 has 20 divisors (see below), whose sum is σ = 24210736. Its totient is φ = 10370808.

The previous prime is 16811369. The next prime is 16811411. The reversal of 16811409 is 90411861.

It is not a de Polignac number, because 16811409 - 2⁷ = 16811281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16811449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 390942 + ... + 390984.

Almost surely, 2^16811409 is an apocalyptic number.

16811409 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

16811409 is a deficient number, since it is larger than the sum of its proper divisors (7399327).

16811409 is an frugal number, since it uses more digits than its factorization.

16811409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 16811409 is about 4100.1718256678. The cubic root of 16811409 is about 256.1737965755.

The spelling of 16811409 in words is "sixteen million, eight hundred eleven thousand, four hundred nine".