128381567 has 4 divisors (see below), whose sum is σ = 128800056. Its totient is φ = 127963080.

The previous prime is 128381563. The next prime is 128381587. The reversal of 128381567 is 765183821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128381567 - 2² = 128381563 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128381563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 208784 + ... + 209397.

It is an arithmetic number, because the mean of its divisors is an integer number (32200014).

Almost surely, 2^128381567 is an apocalyptic number.

128381567 is a deficient number, since it is larger than the sum of its proper divisors (418489).

128381567 is an equidigital number, since it uses as much as digits as its factorization.

128381567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418488.

The product of its digits is 80640, while the sum is 41.

The square root of 128381567 is about 11330.5589888584. The cubic root of 128381567 is about 504.4686984855.

The spelling of 128381567 in words is "one hundred twenty-eight million, three hundred eighty-one thousand, five hundred sixty-seven".