221639066 has 16 divisors (see below), whose sum is σ = 381771360. Its totient is φ = 95442480.

The previous prime is 221639039. The next prime is 221639069. The reversal of 221639066 is 660936122.

221639066 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (221639069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 264701 + ... + 265536.

It is an arithmetic number, because the mean of its divisors is an integer number (23860710).

Almost surely, 2^221639066 is an apocalyptic number.

221639066 is a deficient number, since it is larger than the sum of its proper divisors (160132294).

221639066 is a wasteful number, since it uses less digits than its factorization.

221639066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530269.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 221639066 is about 14887.5473466921. The cubic root of 221639066 is about 605.1765675476.

The spelling of 221639066 in words is "two hundred twenty-one million, six hundred thirty-nine thousand, sixty-six".