28569569 has 16 divisors (see below), whose sum is σ = 33985536. Its totient is φ = 23525280.

The previous prime is 28569557. The next prime is 28569577. The reversal of 28569569 is 96596582.

It is a de Polignac number, because none of the positive numbers 2^k-28569569 is a prime.

It is a super-2 number, since 2×28569569² = 1632440545691522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28569599) 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 in 15 ways as a sum of consecutive naturals, for example, 208469 + ... + 208605.

It is an arithmetic number, because the mean of its divisors is an integer number (2124096).

Almost surely, 2^28569569 is an apocalyptic number.

It is an amenable number.

28569569 is a deficient number, since it is larger than the sum of its proper divisors (5415967).

28569569 is an frugal number, since it uses more digits than its factorization.

28569569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237 (or 175 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 50.

The square root of 28569569 is about 5345.0508884388. The cubic root of 28569569 is about 305.7040761952.

The spelling of 28569569 in words is "twenty-eight million, five hundred sixty-nine thousand, five hundred sixty-nine".