18799340221 has 4 divisors (see below), whose sum is σ = 19788779200. Its totient is φ = 17809901244.

The previous prime is 18799340177. The next prime is 18799340239. The reversal of 18799340221 is 12204399781.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18799340221 - 2⁷ = 18799340093 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 (18799340321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 494719461 + ... + 494719498.

It is an arithmetic number, because the mean of its divisors is an integer number (4947194800).

Almost surely, 2^18799340221 is an apocalyptic number.

It is an amenable number.

18799340221 is a deficient number, since it is larger than the sum of its proper divisors (989438979).

18799340221 is an equidigital number, since it uses as much as digits as its factorization.

18799340221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989438978.

The product of its (nonzero) digits is 217728, while the sum is 46.

The spelling of 18799340221 in words is "eighteen billion, seven hundred ninety-nine million, three hundred forty thousand, two hundred twenty-one".