221166612 has 120 divisors (see below), whose sum is σ = 625695840. Its totient is φ = 67884480.

The previous prime is 221166611. The next prime is 221166641. The reversal of 221166612 is 216661122.

221166612 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221166611) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 227287 + ... + 228257.

It is an arithmetic number, because the mean of its divisors is an integer number (5214132).

Almost surely, 2^221166612 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221166612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312847920).

221166612 is an abundant number, since it is smaller than the sum of its proper divisors (404529228).

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

221166612 is a wasteful number, since it uses less digits than its factorization.

221166612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043 (or 1032 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 221166612 is about 14871.6714595233. The cubic root of 221166612 is about 604.7462560898.

The spelling of 221166612 in words is "two hundred twenty-one million, one hundred sixty-six thousand, six hundred twelve".