16918409 has 8 divisors (see below), whose sum is σ = 17831232. Its totient is φ = 16020400.

The previous prime is 16918399. The next prime is 16918423. The reversal of 16918409 is 90481961.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16918409 - 2¹⁶ = 16852873 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16918439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1319 + ... + 5964.

It is an arithmetic number, because the mean of its divisors is an integer number (2228904).

Almost surely, 2^16918409 is an apocalyptic number.

It is an amenable number.

16918409 is a deficient number, since it is larger than the sum of its proper divisors (912823).

16918409 is a wasteful number, since it uses less digits than its factorization.

16918409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7407.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 16918409 is about 4113.1993630263. The cubic root of 16918409 is about 256.7161395236.

Adding to 16918409 its product of nonzero digits (15552), we get a palindrome (16933961).

The spelling of 16918409 in words is "sixteen million, nine hundred eighteen thousand, four hundred nine".