166027808221 has 4 divisors (see below), whose sum is σ = 181121245344. Its totient is φ = 150934371100.

The previous prime is 166027808197. The next prime is 166027808231. The reversal of 166027808221 is 122808720661.

It is a happy number.

166027808221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 166027808221 - 2⁵ = 166027808189 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 (166027808231) 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 3 ways as a sum of consecutive naturals, for example, 7546718545 + ... + 7546718566.

It is an arithmetic number, because the mean of its divisors is an integer number (45280311336).

Almost surely, 2^166027808221 is an apocalyptic number.

166027808221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

166027808221 is a deficient number, since it is larger than the sum of its proper divisors (15093437123).

166027808221 is a wasteful number, since it uses less digits than its factorization.

166027808221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15093437122.

The product of its (nonzero) digits is 129024, while the sum is 43.

The spelling of 166027808221 in words is "one hundred sixty-six billion, twenty-seven million, eight hundred eight thousand, two hundred twenty-one".