128017391 has 2 divisors, whose sum is σ = 128017392. Its totient is φ = 128017390.

The previous prime is 128017363. The next prime is 128017411. The reversal of 128017391 is 193710821.

It is a strong prime.

It is an emirp because it is prime and its reverse (193710821) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128017391 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 (128017301) 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, 64008695 + 64008696.

It is an arithmetic number, because the mean of its divisors is an integer number (64008696).

Almost surely, 2^128017391 is an apocalyptic number.

128017391 is a deficient number, since it is larger than the sum of its proper divisors (1).

128017391 is an equidigital number, since it uses as much as digits as its factorization.

128017391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 128017391 is about 11314.4770537573. The cubic root of 128017391 is about 503.9912431816.

The spelling of 128017391 in words is "one hundred twenty-eight million, seventeen thousand, three hundred ninety-one".