128998139 has 2 divisors, whose sum is σ = 128998140. Its totient is φ = 128998138.

The previous prime is 128998123. The next prime is 128998147. The reversal of 128998139 is 931899821.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128998139 - 2⁴ = 128998123 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 (128998739) 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, 64499069 + 64499070.

It is an arithmetic number, because the mean of its divisors is an integer number (64499070).

Almost surely, 2^128998139 is an apocalyptic number.

128998139 is a deficient number, since it is larger than the sum of its proper divisors (1).

128998139 is an equidigital number, since it uses as much as digits as its factorization.

128998139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 50.

The square root of 128998139 is about 11357.7347653482. The cubic root of 128998139 is about 505.2750049384.

The spelling of 128998139 in words is "one hundred twenty-eight million, nine hundred ninety-eight thousand, one hundred thirty-nine".