128605679 has 2 divisors, whose sum is σ = 128605680. Its totient is φ = 128605678.

The previous prime is 128605669. The next prime is 128605681. The reversal of 128605679 is 976506821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128605679 - 2⁸ = 128605423 is a prime.

It is a Sophie Germain prime.

Together with 128605681, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128605619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64302839 + 64302840.

It is an arithmetic number, because the mean of its divisors is an integer number (64302840).

Almost surely, 2^128605679 is an apocalyptic number.

128605679 is a deficient number, since it is larger than the sum of its proper divisors (1).

128605679 is an equidigital number, since it uses as much as digits as its factorization.

128605679 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 128605679 is about 11340.4443916453. Note that the first 3 decimals coincide. The cubic root of 128605679 is about 504.7620733270.

The spelling of 128605679 in words is "one hundred twenty-eight million, six hundred five thousand, six hundred seventy-nine".