20128569 has 8 divisors (see below), whose sum is σ = 27099072. Its totient is φ = 13288560.

The previous prime is 20128553. The next prime is 20128573. The reversal of 20128569 is 96582102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20128569 - 2⁴ = 20128553 is a prime.

It is a super-2 number, since 2×20128569² = 810318579975522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20128529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32262 + ... + 32879.

It is an arithmetic number, because the mean of its divisors is an integer number (3387384).

Almost surely, 2^20128569 is an apocalyptic number.

It is an amenable number.

20128569 is a deficient number, since it is larger than the sum of its proper divisors (6970503).

20128569 is a wasteful number, since it uses less digits than its factorization.

20128569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65247.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 20128569 is about 4486.4873787853. The cubic root of 20128569 is about 272.0221696535.

The spelling of 20128569 in words is "twenty million, one hundred twenty-eight thousand, five hundred sixty-nine".