221103666 has 96 divisors (see below), whose sum is σ = 585636480. Its totient is φ = 58848768.

The previous prime is 221103637. The next prime is 221103691. The reversal of 221103666 is 666301122.

221103666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×221103666² = 97773662237279112, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 233005 + ... + 233951.

It is an arithmetic number, because the mean of its divisors is an integer number (6100380).

Almost surely, 2^221103666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221103666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (292818240).

221103666 is an abundant number, since it is smaller than the sum of its proper divisors (364532814).

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

221103666 is a wasteful number, since it uses less digits than its factorization.

221103666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088 (or 1085 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 221103666 is about 14869.5550034290. Note that the first 3 decimals coincide. The cubic root of 221103666 is about 604.6888785779.

Adding to 221103666 its reverse (666301122), we get a palindrome (887404788).

The spelling of 221103666 in words is "two hundred twenty-one million, one hundred three thousand, six hundred sixty-six".