128918771 has 2 divisors, whose sum is σ = 128918772. Its totient is φ = 128918770.

The previous prime is 128918731. The next prime is 128918821. The reversal of 128918771 is 177819821.

It is a weak prime.

It is an emirp because it is prime and its reverse (177819821) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128918771 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (128918711) 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, 64459385 + 64459386.

It is an arithmetic number, because the mean of its divisors is an integer number (64459386).

Almost surely, 2^128918771 is an apocalyptic number.

128918771 is a deficient number, since it is larger than the sum of its proper divisors (1).

128918771 is an equidigital number, since it uses as much as digits as its factorization.

128918771 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56448, while the sum is 44.

The square root of 128918771 is about 11354.2402211685. The cubic root of 128918771 is about 505.1713577222.

The spelling of 128918771 in words is "one hundred twenty-eight million, nine hundred eighteen thousand, seven hundred seventy-one".