111111109 has 2 divisors, whose sum is σ = 111111110. Its totient is φ = 111111108.

The previous prime is 111111089. The next prime is 111111113. The reversal of 111111109 is 901111111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99700225 + 11410884 = 9985^2 + 3378^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111111109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111111092 and 111111101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111111139) 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 as a sum of consecutive naturals, namely, 55555554 + 55555555.

It is an arithmetic number, because the mean of its divisors is an integer number (55555555).

Almost surely, 2^111111109 is an apocalyptic number.

It is an amenable number.

111111109 is a deficient number, since it is larger than the sum of its proper divisors (1).

111111109 is an equidigital number, since it uses as much as digits as its factorization.

111111109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9, while the sum is 16.

The square root of 111111109 is about 10540.9254337558. The cubic root of 111111109 is about 480.7498537244.

The spelling of 111111109 in words is "one hundred eleven million, one hundred eleven thousand, one hundred nine".