221066171 has 4 divisors (see below), whose sum is σ = 221100600. Its totient is φ = 221031744.

The previous prime is 221066149. The next prime is 221066189. The reversal of 221066171 is 171660122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221066171 - 2⁶ = 221066107 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221066171.

It is not an unprimeable number, because it can be changed into a prime (221066141) 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 3 ways as a sum of consecutive naturals, for example, 4406 + ... + 21483.

It is an arithmetic number, because the mean of its divisors is an integer number (55275150).

Almost surely, 2^221066171 is an apocalyptic number.

221066171 is a deficient number, since it is larger than the sum of its proper divisors (34429).

221066171 is an equidigital number, since it uses as much as digits as its factorization.

221066171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34428.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 221066171 is about 14868.2941523229. The cubic root of 221066171 is about 604.6546953798.

The spelling of 221066171 in words is "two hundred twenty-one million, sixty-six thousand, one hundred seventy-one".