18666493 has 8 divisors (see below), whose sum is σ = 20805120. Its totient is φ = 16643520.

The previous prime is 18666481. The next prime is 18666497. The reversal of 18666493 is 39466681.

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 18666493 - 2⁹ = 18665981 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 (18666497) 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, 28573 + ... + 29218.

It is an arithmetic number, because the mean of its divisors is an integer number (2600640).

Almost surely, 2^18666493 is an apocalyptic number.

It is an amenable number.

18666493 is a deficient number, since it is larger than the sum of its proper divisors (2138627).

18666493 is a wasteful number, since it uses less digits than its factorization.

18666493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57827.

The product of its digits is 186624, while the sum is 43.

The square root of 18666493 is about 4320.4737008805. The cubic root of 18666493 is about 265.2696578696.

The spelling of 18666493 in words is "eighteen million, six hundred sixty-six thousand, four hundred ninety-three".