221073666 has 16 divisors (see below), whose sum is σ = 482342688. Its totient is φ = 66992000.

The previous prime is 221073647. The next prime is 221073667. The reversal of 221073666 is 666370122.

221073666 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221073667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1674735 + ... + 1674866.

It is an arithmetic number, because the mean of its divisors is an integer number (30146418).

Almost surely, 2^221073666 is an apocalyptic number.

221073666 is an abundant number, since it is smaller than the sum of its proper divisors (261269022).

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

221073666 is a wasteful number, since it uses less digits than its factorization.

221073666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3349617.

The product of its (nonzero) digits is 18144, while the sum is 33.

The square root of 221073666 is about 14868.5461965856. The cubic root of 221073666 is about 604.6615286818.

The spelling of 221073666 in words is "two hundred twenty-one million, seventy-three thousand, six hundred sixty-six".