18805908221 has 8 divisors (see below), whose sum is σ = 19246671360. Its totient is φ = 18368327952.

The previous prime is 18805908161. The next prime is 18805908223. The reversal of 18805908221 is 12280950881.

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 18805908221 - 2¹⁸ = 18805646077 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 (18805908223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 783761 + ... + 807398.

It is an arithmetic number, because the mean of its divisors is an integer number (2405833920).

Almost surely, 2^18805908221 is an apocalyptic number.

It is an amenable number.

18805908221 is a deficient number, since it is larger than the sum of its proper divisors (440763139).

18805908221 is a wasteful number, since it uses less digits than its factorization.

18805908221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1591435.

The product of its (nonzero) digits is 92160, while the sum is 44.

The spelling of 18805908221 in words is "eighteen billion, eight hundred five million, nine hundred eight thousand, two hundred twenty-one".