11111111099989 has 2 divisors, whose sum is σ = 11111111099990. Its totient is φ = 11111111099988.

The previous prime is 11111111099987. The next prime is 11111111100071. The reversal of 11111111099989 is 98999011111111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8623519715889 + 2487591384100 = 2936583^2 + 1577210^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111111099989 - 2¹ = 11111111099987 is a prime.

Together with 11111111099987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11111111099987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555555549994 + 5555555549995.

It is an arithmetic number, because the mean of its divisors is an integer number (5555555549995).

Almost surely, 2^{11111111099989} is an apocalyptic number.

It is an amenable number.

11111111099989 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111111099989 is an equidigital number, since it uses as much as digits as its factorization.

11111111099989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52488, while the sum is 52.

The spelling of 11111111099989 in words is "eleven trillion, one hundred eleven billion, one hundred eleven million, ninety-nine thousand, nine hundred eighty-nine".