111111011101111 has 4 divisors (see below), whose sum is σ = 126984012686992. Its totient is φ = 95238009515232.

The previous prime is 111111011101067. The next prime is 111111011101117. The reversal of 111111011101111 is 111101110111111.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 111111011101111 - 2¹⁹ = 111111010576823 is a prime.

It is a super-2 number, since 2×111111011101111² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111111011101091 and 111111011101100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111011101117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7936500792930 + ... + 7936500792943.

It is an arithmetic number, because the mean of its divisors is an integer number (31746003171748).

Almost surely, 2^{111111011101111} is an apocalyptic number.

111111011101111 is a deficient number, since it is larger than the sum of its proper divisors (15873001585881).

111111011101111 is an equidigital number, since it uses as much as digits as its factorization.

111111011101111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15873001585880.

The product of its (nonzero) digits is 1, while the sum is 13.

Adding to 111111011101111 its reverse (111101110111111), we get a palindrome (222212121212222).

It can be divided in two parts, 11 and 1111011101111, that multiplied together give a palindrome (12221122112221).

The spelling of 111111011101111 in words is "one hundred eleven trillion, one hundred eleven billion, eleven million, one hundred one thousand, one hundred eleven".