221166165 has 16 divisors (see below), whose sum is σ = 386035776. Its totient is φ = 107232000.

The previous prime is 221166119. The next prime is 221166167. The reversal of 221166165 is 561661122.

It is not a de Polignac number, because 221166165 - 2⁹ = 221165653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221166167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 670036 + ... + 670365.

It is an arithmetic number, because the mean of its divisors is an integer number (24127236).

Almost surely, 2^221166165 is an apocalyptic number.

It is an amenable number.

221166165 is a deficient number, since it is larger than the sum of its proper divisors (164869611).

221166165 is a wasteful number, since it uses less digits than its factorization.

221166165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340420.

The product of its digits is 4320, while the sum is 30.

The square root of 221166165 is about 14871.6564309427. The cubic root of 221166165 is about 604.7458486718.

The spelling of 221166165 in words is "two hundred twenty-one million, one hundred sixty-six thousand, one hundred sixty-five".