18389666 has 8 divisors (see below), whose sum is σ = 28330140. Its totient is φ = 8946288.

The previous prime is 18389653. The next prime is 18389677. The reversal of 18389666 is 66698381.

It can be written as a sum of positive squares in 2 ways, for example, as 18241441 + 148225 = 4271^2 + 385^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 18389666.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124181 + ... + 124328.

Almost surely, 2^18389666 is an apocalyptic number.

18389666 is a deficient number, since it is larger than the sum of its proper divisors (9940474).

18389666 is a wasteful number, since it uses less digits than its factorization.

18389666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248548.

The product of its digits is 373248, while the sum is 47.

The square root of 18389666 is about 4288.3173856421. The cubic root of 18389666 is about 263.9517913962.

The spelling of 18389666 in words is "eighteen million, three hundred eighty-nine thousand, six hundred sixty-six".