221166 has 24 divisors (see below), whose sum is σ = 523224. Its totient is φ = 66960.

The previous prime is 221159. The next prime is 221171. The reversal of 221166 is 661122.

It is a happy number.

221166 is nontrivially palindromic in base 8.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is a Curzon number.

It is a zygodrome in base 10.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 221166.

It is an unprimeable number.

221166 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 361 + ... + 756.

It is an arithmetic number, because the mean of its divisors is an integer number (21801).

2²²¹¹⁶⁶ is an apocalyptic number.

221166 is an abundant number, since it is smaller than the sum of its proper divisors (302058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221166 is a wasteful number, since it uses less digits than its factorization.

221166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1136 (or 1133 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 221166 is about 470.2828935864. The cubic root of 221166 is about 60.4745698282.

Adding to 221166 its reverse (661122), we get a palindrome (882288).

It can be divided in two parts, 22116 and 6, that added together give a palindrome (22122).

The spelling of 221166 in words is "two hundred twenty-one thousand, one hundred sixty-six".