128381549 has 2 divisors, whose sum is σ = 128381550. Its totient is φ = 128381548.

The previous prime is 128381503. The next prime is 128381563. The reversal of 128381549 is 945183821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65496649 + 62884900 = 8093^2 + 7930^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128381549 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 (128381249) 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, 64190774 + 64190775.

It is an arithmetic number, because the mean of its divisors is an integer number (64190775).

Almost surely, 2^128381549 is an apocalyptic number.

It is an amenable number.

128381549 is a deficient number, since it is larger than the sum of its proper divisors (1).

128381549 is an equidigital number, since it uses as much as digits as its factorization.

128381549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 41.

The square root of 128381549 is about 11330.5581945463. The cubic root of 128381549 is about 504.4686749088.

The spelling of 128381549 in words is "one hundred twenty-eight million, three hundred eighty-one thousand, five hundred forty-nine".