221991222 has 16 divisors (see below), whose sum is σ = 445258800. Its totient is φ = 73784352.

The previous prime is 221991221. The next prime is 221991247. The reversal of 221991222 is 222199122.

It is a self number, because there is not a number n which added to its sum of digits gives 221991222.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221991221) 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, 50913 + ... + 55100.

It is an arithmetic number, because the mean of its divisors is an integer number (27828675).

Almost surely, 2^221991222 is an apocalyptic number.

221991222 is an abundant number, since it is smaller than the sum of its proper divisors (223267578).

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

221991222 is a wasteful number, since it uses less digits than its factorization.

221991222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106367.

The product of its digits is 2592, while the sum is 30.

The square root of 221991222 is about 14899.3698524468. The cubic root of 221991222 is about 605.4969138823.

The spelling of 221991222 in words is "two hundred twenty-one million, nine hundred ninety-one thousand, two hundred twenty-two".