221323206 has 16 divisors (see below), whose sum is σ = 476696304. Its totient is φ = 68099424.

The previous prime is 221323171. The next prime is 221323211. The reversal of 221323206 is 602323122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1418661 + ... + 1418816.

It is an arithmetic number, because the mean of its divisors is an integer number (29793519).

Almost surely, 2^221323206 is an apocalyptic number.

221323206 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

221323206 is an abundant number, since it is smaller than the sum of its proper divisors (255373098).

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

221323206 is a wasteful number, since it uses less digits than its factorization.

221323206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2837495.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 221323206 is about 14876.9353698939. The cubic root of 221323206 is about 604.8889498609. Note that the first 3 decimals are identical.

Adding to 221323206 its reverse (602323122), we get a palindrome (823646328).

The spelling of 221323206 in words is "two hundred twenty-one million, three hundred twenty-three thousand, two hundred six".