111221111 has 4 divisors (see below), whose sum is σ = 111251424. Its totient is φ = 111190800.

The previous prime is 111221101. The next prime is 111221141. The reversal of 111221111 is 111122111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 111122111 = 79 ⋅1406609.

It is a cyclic number.

It is not a de Polignac number, because 111221111 - 2²² = 107026807 is a prime.

It is a Duffinian number.

It is a zygodrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 111221092 and 111221101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111221101) 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, 8750 + ... + 17291.

It is an arithmetic number, because the mean of its divisors is an integer number (27812856).

Almost surely, 2^111221111 is an apocalyptic number.

111221111 is a deficient number, since it is larger than the sum of its proper divisors (30313).

111221111 is an equidigital number, since it uses as much as digits as its factorization.

111221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30312.

The product of its digits is 4, while the sum is 11.

The square root of 111221111 is about 10546.1419960097. The cubic root of 111221111 is about 480.9084517368.

Adding to 111221111 its reverse (111122111), we get a palindrome (222343222).

The spelling of 111221111 in words is "one hundred eleven million, two hundred twenty-one thousand, one hundred eleven".