111445861 has 2 divisors, whose sum is σ = 111445862. Its totient is φ = 111445860.

The previous prime is 111445823. The next prime is 111445907. The reversal of 111445861 is 168544111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 93721761 + 17724100 = 9681^2 + 4210^2 .

It is an emirp because it is prime and its reverse (168544111) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111445861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111445661) 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 as a sum of consecutive naturals, namely, 55722930 + 55722931.

It is an arithmetic number, because the mean of its divisors is an integer number (55722931).

Almost surely, 2^111445861 is an apocalyptic number.

It is an amenable number.

111445861 is a deficient number, since it is larger than the sum of its proper divisors (1).

111445861 is an equidigital number, since it uses as much as digits as its factorization.

111445861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3840, while the sum is 31.

The square root of 111445861 is about 10556.7921737619. The cubic root of 111445861 is about 481.2321656178.

Adding to 111445861 its reverse (168544111), we get a palindrome (279989972).

The spelling of 111445861 in words is "one hundred eleven million, four hundred forty-five thousand, eight hundred sixty-one".