128569081 has 4 divisors (see below), whose sum is σ = 128847232. Its totient is φ = 128290932.

The previous prime is 128569037. The next prime is 128569087. The reversal of 128569081 is 180965821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 180965821 = 2887 ⋅62683.

It is a cyclic number.

It is not a de Polignac number, because 128569081 - 2¹⁵ = 128536313 is a prime.

It is a super-2 number, since 2×128569081² = 33060017178369122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128569087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138381 + ... + 139306.

It is an arithmetic number, because the mean of its divisors is an integer number (32211808).

Almost surely, 2^128569081 is an apocalyptic number.

It is an amenable number.

128569081 is a deficient number, since it is larger than the sum of its proper divisors (278151).

128569081 is an equidigital number, since it uses as much as digits as its factorization.

128569081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278150.

The product of its (nonzero) digits is 34560, while the sum is 40.

The square root of 128569081 is about 11338.8306716345. The cubic root of 128569081 is about 504.7141878445.

The spelling of 128569081 in words is "one hundred twenty-eight million, five hundred sixty-nine thousand, eighty-one".