111122221 has 4 divisors (see below), whose sum is σ = 126996832. Its totient is φ = 95247612.

The previous prime is 111122213. The next prime is 111122227. The reversal of 111122221 is 122221111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122221111 = 5711 ⋅21401.

It is a cyclic number.

It is not a de Polignac number, because 111122221 - 2³ = 111122213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111122227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7937295 + ... + 7937308.

It is an arithmetic number, because the mean of its divisors is an integer number (31749208).

Almost surely, 2^111122221 is an apocalyptic number.

It is an amenable number.

111122221 is a deficient number, since it is larger than the sum of its proper divisors (15874611).

111122221 is an equidigital number, since it uses as much as digits as its factorization.

111122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15874610.

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

The square root of 111122221 is about 10541.4525090236. The cubic root of 111122221 is about 480.7658794676.

Adding to 111122221 its reverse (122221111), we get a palindrome (233343332).

It can be divided in two parts, 1111 and 22221, that added together give a palindrome (23332).

The spelling of 111122221 in words is "one hundred eleven million, one hundred twenty-two thousand, two hundred twenty-one".