222121111 has 4 divisors (see below), whose sum is σ = 223816824. Its totient is φ = 220425400.

The previous prime is 222121093. The next prime is 222121117. The reversal of 222121111 is 111121222.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 111121222 = 2 ⋅55560611.

It is a cyclic number.

It is not a de Polignac number, because 222121111 - 2²³ = 213732503 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 222121091 and 222121100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222121117) 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, 847660 + ... + 847921.

It is an arithmetic number, because the mean of its divisors is an integer number (55954206).

Almost surely, 2^222121111 is an apocalyptic number.

222121111 is a deficient number, since it is larger than the sum of its proper divisors (1695713).

222121111 is a wasteful number, since it uses less digits than its factorization.

222121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1695712.

The product of its digits is 16, while the sum is 13.

The square root of 222121111 is about 14903.7280906490. The cubic root of 222121111 is about 605.6149846989.

Adding to 222121111 its reverse (111121222), we get a palindrome (333242333).

It can be divided in two parts, 2221211 and 11, that added together give a palindrome (2221222).

The spelling of 222121111 in words is "two hundred twenty-two million, one hundred twenty-one thousand, one hundred eleven".