111222111221 has 16 divisors (see below), whose sum is σ = 120598749936. Its totient is φ = 101964043776.

The previous prime is 111222111173. The next prime is 111222111229. The reversal of 111222111221 is 122111222111.

It can be written as a sum of positive squares in 8 ways, for example, as 6796188721 + 104425922500 = 82439^2 + 323150^2 .

It is a cyclic number.

It is not a de Polignac number, because 111222111221 - 2²² = 111217916917 is a prime.

It is a super-2 number, since 2×111222111221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 111222111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111222111229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2117351 + ... + 2169243.

It is an arithmetic number, because the mean of its divisors is an integer number (7537421871).

Almost surely, 2^111222111221 is an apocalyptic number.

It is an amenable number.

111222111221 is a deficient number, since it is larger than the sum of its proper divisors (9376638715).

111222111221 is a wasteful number, since it uses less digits than its factorization.

111222111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53032.

The product of its digits is 32, while the sum is 17.

Adding to 111222111221 its reverse (122111222111), we get a palindrome (233333333332).

The spelling of 111222111221 in words is "one hundred eleven billion, two hundred twenty-two million, one hundred eleven thousand, two hundred twenty-one".