128689019 has 2 divisors, whose sum is σ = 128689020. Its totient is φ = 128689018.

The previous prime is 128689013. The next prime is 128689039. The reversal of 128689019 is 910986821.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128689019 is a prime.

It is a super-2 number, since 2×128689019² = 33121727222364722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128689013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64344509 + 64344510.

It is an arithmetic number, because the mean of its divisors is an integer number (64344510).

Almost surely, 2^128689019 is an apocalyptic number.

128689019 is a deficient number, since it is larger than the sum of its proper divisors (1).

128689019 is an equidigital number, since it uses as much as digits as its factorization.

128689019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 44.

The square root of 128689019 is about 11344.1182557306. The cubic root of 128689019 is about 504.8710829964.

The spelling of 128689019 in words is "one hundred twenty-eight million, six hundred eighty-nine thousand, nineteen".