128189687 has 2 divisors, whose sum is σ = 128189688. Its totient is φ = 128189686.

The previous prime is 128189641. The next prime is 128189723. The reversal of 128189687 is 786981821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128189687 - 2¹⁰ = 128188663 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128189627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64094843 + 64094844.

It is an arithmetic number, because the mean of its divisors is an integer number (64094844).

Almost surely, 2^128189687 is an apocalyptic number.

128189687 is a deficient number, since it is larger than the sum of its proper divisors (1).

128189687 is an equidigital number, since it uses as much as digits as its factorization.

128189687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 387072, while the sum is 50.

The square root of 128189687 is about 11322.0884557576. The cubic root of 128189687 is about 504.2172456720.

The spelling of 128189687 in words is "one hundred twenty-eight million, one hundred eighty-nine thousand, six hundred eighty-seven".