18668670221 has 12 divisors (see below), whose sum is σ = 19352254272. Its totient is φ = 18008480784.

The previous prime is 18668670217. The next prime is 18668670227. The reversal of 18668670221 is 12207686681.

It is not a de Polignac number, because 18668670221 - 2² = 18668670217 is a prime.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18668670227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 968540 + ... + 987626.

It is an arithmetic number, because the mean of its divisors is an integer number (1612687856).

Almost surely, 2^18668670221 is an apocalyptic number.

It is an amenable number.

18668670221 is a deficient number, since it is larger than the sum of its proper divisors (683584051).

18668670221 is a wasteful number, since it uses less digits than its factorization.

18668670221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20308 (or 20279 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 47.

The spelling of 18668670221 in words is "eighteen billion, six hundred sixty-eight million, six hundred seventy thousand, two hundred twenty-one".