16646393 has 4 divisors (see below), whose sum is σ = 16746240. Its totient is φ = 16546548.

The previous prime is 16646381. The next prime is 16646401. The reversal of 16646393 is 39364661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16646393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16646323) 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 3 ways as a sum of consecutive naturals, for example, 49673 + ... + 50006.

It is an arithmetic number, because the mean of its divisors is an integer number (4186560).

Almost surely, 2^16646393 is an apocalyptic number.

It is an amenable number.

16646393 is a deficient number, since it is larger than the sum of its proper divisors (99847).

16646393 is an equidigital number, since it uses as much as digits as its factorization.

16646393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99846.

The product of its digits is 69984, while the sum is 38.

The square root of 16646393 is about 4079.9991421568. Note that the first 3 decimals coincide. The cubic root of 16646393 is about 255.3328627602.

The spelling of 16646393 in words is "sixteen million, six hundred forty-six thousand, three hundred ninety-three".