128798209 has 2 divisors, whose sum is σ = 128798210. Its totient is φ = 128798208.

The previous prime is 128798177. The next prime is 128798213. The reversal of 128798209 is 902897821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127757809 + 1040400 = 11303^2 + 1020^2 .

It is a cyclic number.

It is not a de Polignac number, because 128798209 - 2⁵ = 128798177 is a prime.

It is not a weakly prime, because it can be changed into another prime (128795209) 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, 64399104 + 64399105.

It is an arithmetic number, because the mean of its divisors is an integer number (64399105).

Almost surely, 2^128798209 is an apocalyptic number.

It is an amenable number.

128798209 is a deficient number, since it is larger than the sum of its proper divisors (1).

128798209 is an equidigital number, since it uses as much as digits as its factorization.

128798209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 128798209 is about 11348.9298614451. The cubic root of 128798209 is about 505.0138335589.

The spelling of 128798209 in words is "one hundred twenty-eight million, seven hundred ninety-eight thousand, two hundred nine".