16693309 has 4 divisors (see below), whose sum is σ = 16701916. Its totient is φ = 16684704.

The previous prime is 16693301. The next prime is 16693349. The reversal of 16693309 is 90339661.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 13344409 + 3348900 = 3653^2 + 1830^2 .

It is a cyclic number.

It is not a de Polignac number, because 16693309 - 2³ = 16693301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16693301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127 + ... + 5779.

It is an arithmetic number, because the mean of its divisors is an integer number (4175479).

Almost surely, 2^16693309 is an apocalyptic number.

It is an amenable number.

16693309 is a deficient number, since it is larger than the sum of its proper divisors (8607).

16693309 is an equidigital number, since it uses as much as digits as its factorization.

16693309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8606.

The product of its (nonzero) digits is 26244, while the sum is 37.

The square root of 16693309 is about 4085.7446077796. The cubic root of 16693309 is about 255.5725134795.

The spelling of 16693309 in words is "sixteen million, six hundred ninety-three thousand, three hundred nine".