222555221 has 4 divisors (see below), whose sum is σ = 254348832. Its totient is φ = 190761612.

The previous prime is 222555197. The next prime is 222555241. The reversal of 222555221 is 122555222.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 222555221 - 2²² = 218360917 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222555241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15896795 + ... + 15896808.

It is an arithmetic number, because the mean of its divisors is an integer number (63587208).

Almost surely, 2^222555221 is an apocalyptic number.

It is an amenable number.

222555221 is a deficient number, since it is larger than the sum of its proper divisors (31793611).

222555221 is an equidigital number, since it uses as much as digits as its factorization.

222555221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31793610.

The product of its digits is 4000, while the sum is 26.

The square root of 222555221 is about 14918.2847874680. The cubic root of 222555221 is about 606.0092627484.

Subtracting from 222555221 its reverse (122555222), we obtain a palindrome (99999999).

The spelling of 222555221 in words is "two hundred twenty-two million, five hundred fifty-five thousand, two hundred twenty-one".