128234989 has 2 divisors, whose sum is σ = 128234990. Its totient is φ = 128234988.

The previous prime is 128234969. The next prime is 128235001. The reversal of 128234989 is 989432821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103184964 + 25050025 = 10158^2 + 5005^2 .

It is a cyclic number.

It is not a de Polignac number, because 128234989 - 2⁵ = 128234957 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128234969) 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, 64117494 + 64117495.

It is an arithmetic number, because the mean of its divisors is an integer number (64117495).

Almost surely, 2^128234989 is an apocalyptic number.

It is an amenable number.

128234989 is a deficient number, since it is larger than the sum of its proper divisors (1).

128234989 is an equidigital number, since it uses as much as digits as its factorization.

128234989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 46.

The square root of 128234989 is about 11324.0888816717. The cubic root of 128234989 is about 504.2766351595.

The spelling of 128234989 in words is "one hundred twenty-eight million, two hundred thirty-four thousand, nine hundred eighty-nine".