221111222004 has 36 divisors (see below), whose sum is σ = 558980718660. Its totient is φ = 73695738240.

The previous prime is 221111221999. The next prime is 221111222047. The reversal of 221111222004 is 400222111122.

It can be written as a sum of positive squares in 2 ways, for example, as 69829119504 + 151282102500 = 264252^2 + 388950^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×221111222004² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7512 + ... + 665040.

It is an arithmetic number, because the mean of its divisors is an integer number (15527242185).

Almost surely, 2^221111222004 is an apocalyptic number.

It is an amenable number.

221111222004 is an abundant number, since it is smaller than the sum of its proper divisors (337869496656).

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

221111222004 is a wasteful number, since it uses less digits than its factorization.

221111222004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666880 (or 666875 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221111222004 its reverse (400222111122), we get a palindrome (621333333126).

The spelling of 221111222004 in words is "two hundred twenty-one billion, one hundred eleven million, two hundred twenty-two thousand, four".