111011891 has 2 divisors, whose sum is σ = 111011892. Its totient is φ = 111011890.

The previous prime is 111011861. The next prime is 111011909. The reversal of 111011891 is 198110111.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111011891 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (111011821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55505945 + 55505946.

It is an arithmetic number, because the mean of its divisors is an integer number (55505946).

Almost surely, 2^111011891 is an apocalyptic number.

111011891 is a deficient number, since it is larger than the sum of its proper divisors (1).

111011891 is an equidigital number, since it uses as much as digits as its factorization.

111011891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 23.

The square root of 111011891 is about 10536.2180596265. The cubic root of 111011891 is about 480.6067139901.

The spelling of 111011891 in words is "one hundred eleven million, eleven thousand, eight hundred ninety-one".