128667919 has 2 divisors, whose sum is σ = 128667920. Its totient is φ = 128667918.

The previous prime is 128667901. The next prime is 128667953. The reversal of 128667919 is 919766821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 128667919 - 2²³ = 120279311 is a prime.

It is a super-2 number, since 2×128667919² = 33110866759581122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128667419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64333959 + 64333960.

It is an arithmetic number, because the mean of its divisors is an integer number (64333960).

Almost surely, 2^128667919 is an apocalyptic number.

128667919 is a deficient number, since it is larger than the sum of its proper divisors (1).

128667919 is an equidigital number, since it uses as much as digits as its factorization.

128667919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 49.

The square root of 128667919 is about 11343.1882202492. The cubic root of 128667919 is about 504.8434884065.

The spelling of 128667919 in words is "one hundred twenty-eight million, six hundred sixty-seven thousand, nine hundred nineteen".