128911441 has 4 divisors (see below), whose sum is σ = 132395572. Its totient is φ = 125427312.

The previous prime is 128911429. The next prime is 128911487. The reversal of 128911441 is 144119821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 144119821 = 29 ⋅4969649.

It can be written as a sum of positive squares in 2 ways, for example, as 71757841 + 57153600 = 8471^2 + 7560^2 .

It is a cyclic number.

It is not a de Polignac number, because 128911441 - 2⁷ = 128911313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128914441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1742010 + ... + 1742083.

It is an arithmetic number, because the mean of its divisors is an integer number (33098893).

Almost surely, 2^128911441 is an apocalyptic number.

It is an amenable number.

128911441 is a deficient number, since it is larger than the sum of its proper divisors (3484131).

128911441 is an equidigital number, since it uses as much as digits as its factorization.

128911441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3484130.

The product of its digits is 2304, while the sum is 31.

The square root of 128911441 is about 11353.9174296804. The cubic root of 128911441 is about 505.1617832793.

The spelling of 128911441 in words is "one hundred twenty-eight million, nine hundred eleven thousand, four hundred forty-one".