128272891 has 2 divisors, whose sum is σ = 128272892. Its totient is φ = 128272890.

The previous prime is 128272877. The next prime is 128272943. The reversal of 128272891 is 198272821.

It is a weak prime.

It is an emirp because it is prime and its reverse (198272821) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128272891 is a prime.

It is not a weakly prime, because it can be changed into another prime (128272811) 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, 64136445 + 64136446.

It is an arithmetic number, because the mean of its divisors is an integer number (64136446).

Almost surely, 2^128272891 is an apocalyptic number.

128272891 is a deficient number, since it is larger than the sum of its proper divisors (1).

128272891 is an equidigital number, since it uses as much as digits as its factorization.

128272891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 128272891 is about 11325.7622701521. The cubic root of 128272891 is about 504.3263127355.

The spelling of 128272891 in words is "one hundred twenty-eight million, two hundred seventy-two thousand, eight hundred ninety-one".