11220111 has 24 divisors (see below), whose sum is σ = 18613920. Its totient is φ = 6379776.

The previous prime is 11220107. The next prime is 11220137. The reversal of 11220111 is 11102211.

It is a happy number.

It is not a de Polignac number, because 11220111 - 2² = 11220107 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 11220093 and 11220102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11220151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19435 + ... + 20003.

It is an arithmetic number, because the mean of its divisors is an integer number (775580).

Almost surely, 2^11220111 is an apocalyptic number.

11220111 is a deficient number, since it is larger than the sum of its proper divisors (7393809).

11220111 is a wasteful number, since it uses less digits than its factorization.

11220111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895 (or 892 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 11220111 is about 3349.6434138577. The cubic root of 11220111 is about 223.8716247304.

Adding to 11220111 its reverse (11102211), we get a palindrome (22322322).

The spelling of 11220111 in words is "eleven million, two hundred twenty thousand, one hundred eleven".