18666393 has 8 divisors (see below), whose sum is σ = 24938208. Its totient is φ = 12419424.

The previous prime is 18666383. The next prime is 18666413. The reversal of 18666393 is 39366681.

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

It is not a de Polignac number, because 18666393 - 2¹⁰ = 18665369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18666313) 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 7 ways as a sum of consecutive naturals, for example, 4380 + ... + 7517.

It is an arithmetic number, because the mean of its divisors is an integer number (3117276).

Almost surely, 2^18666393 is an apocalyptic number.

It is an amenable number.

18666393 is a deficient number, since it is larger than the sum of its proper divisors (6271815).

18666393 is a wasteful number, since it uses less digits than its factorization.

18666393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12423.

The product of its digits is 139968, while the sum is 42.

The square root of 18666393 is about 4320.4621280599. The cubic root of 18666393 is about 265.2691841685.

The spelling of 18666393 in words is "eighteen million, six hundred sixty-six thousand, three hundred ninety-three".