111999999989 has 2 divisors, whose sum is σ = 111999999990. Its totient is φ = 111999999988.

The previous prime is 111999999983. The next prime is 112000000003. The reversal of 111999999989 is 989999999111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 101805664900 + 10194335089 = 319070^2 + 100967^2 .

It is a cyclic number.

It is not a de Polignac number, because 111999999989 - 2²⁰ = 111998951413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111999999983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55999999994 + 55999999995.

It is an arithmetic number, because the mean of its divisors is an integer number (55999999995).

Almost surely, 2^111999999989 is an apocalyptic number.

It is an amenable number.

111999999989 is a deficient number, since it is larger than the sum of its proper divisors (1).

111999999989 is an equidigital number, since it uses as much as digits as its factorization.

111999999989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 344373768, while the sum is 83.

The spelling of 111999999989 in words is "one hundred eleven billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-nine".