128923187 has 2 divisors, whose sum is σ = 128923188. Its totient is φ = 128923186.

The previous prime is 128923177. The next prime is 128923217. The reversal of 128923187 is 781329821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 128923187 - 2⁸ = 128922931 is a prime.

It is not a weakly prime, because it can be changed into another prime (128923117) 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, 64461593 + 64461594.

It is an arithmetic number, because the mean of its divisors is an integer number (64461594).

Almost surely, 2^128923187 is an apocalyptic number.

128923187 is a deficient number, since it is larger than the sum of its proper divisors (1).

128923187 is an equidigital number, since it uses as much as digits as its factorization.

128923187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 41.

The square root of 128923187 is about 11354.4346842985. The cubic root of 128923187 is about 505.1771257243.

The spelling of 128923187 in words is "one hundred twenty-eight million, nine hundred twenty-three thousand, one hundred eighty-seven".