128912779 has 2 divisors, whose sum is σ = 128912780. Its totient is φ = 128912778.

The previous prime is 128912767. The next prime is 128912807. The reversal of 128912779 is 977219821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 128912779 - 2¹¹ = 128910731 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128912759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64456389 + 64456390.

It is an arithmetic number, because the mean of its divisors is an integer number (64456390).

Almost surely, 2^128912779 is an apocalyptic number.

128912779 is a deficient number, since it is larger than the sum of its proper divisors (1).

128912779 is an equidigital number, since it uses as much as digits as its factorization.

128912779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 46.

The square root of 128912779 is about 11353.9763519218. The cubic root of 128912779 is about 505.1635310014.

The spelling of 128912779 in words is "one hundred twenty-eight million, nine hundred twelve thousand, seven hundred seventy-nine".