11121111 has 16 divisors (see below), whose sum is σ = 17445600. Its totient is φ = 6977664.

The previous prime is 11121083. The next prime is 11121139. The reversal of 11121111 is 11112111.

It is an interprime number because it is at equal distance from previous prime (11121083) and next prime (11121139).

It is not a de Polignac number, because 11121111 - 2¹¹ = 11119063 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 = 11121093 and 11121102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11121611) 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, 11656 + ... + 12573.

It is an arithmetic number, because the mean of its divisors is an integer number (1090350).

Almost surely, 2^11121111 is an apocalyptic number.

11121111 is a deficient number, since it is larger than the sum of its proper divisors (6324489).

11121111 is a wasteful number, since it uses less digits than its factorization.

11121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24255 (or 24249 counting only the distinct ones).

The product of its digits is 2, while the sum is 9.

The square root of 11121111 is about 3334.8329793260. The cubic root of 11121111 is about 223.2112391727.

Adding to 11121111 its reverse (11112111), we get a palindrome (22233222).

The spelling of 11121111 in words is "eleven million, one hundred twenty-one thousand, one hundred eleven".