221222222 has 8 divisors (see below), whose sum is σ = 357359016. Its totient is φ = 102102552.

The previous prime is 221222213. The next prime is 221222249. The reversal of 221222222 is 222222122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a nude number because it is divisible by every one of its digits.

221222222 is a modest number, since divided by 22222 gives 2212 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 221222222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4254248 + ... + 4254299.

It is an arithmetic number, because the mean of its divisors is an integer number (44669877).

Almost surely, 2^221222222 is an apocalyptic number.

221222222 is a deficient number, since it is larger than the sum of its proper divisors (136136794).

221222222 is a wasteful number, since it uses less digits than its factorization.

221222222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8508562.

The product of its digits is 256, while the sum is 17.

The square root of 221222222 is about 14873.5410040783. The cubic root of 221222222 is about 604.7969375207.

Adding to 221222222 its reverse (222222122), we get a palindrome (443444344).

The spelling of 221222222 in words is "two hundred twenty-one million, two hundred twenty-two thousand, two hundred twenty-two".