28531569 has 16 divisors (see below), whose sum is σ = 43305984. Its totient is φ = 16539600.

The previous prime is 28531541. The next prime is 28531571. The reversal of 28531569 is 96513582.

It is not a de Polignac number, because 28531569 - 2⁵ = 28531537 is a prime.

It is a super-2 number, since 2×28531569² = 1628100859203522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28531579) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18037 + ... + 19554.

It is an arithmetic number, because the mean of its divisors is an integer number (2706624).

Almost surely, 2^28531569 is an apocalyptic number.

It is an amenable number.

28531569 is a deficient number, since it is larger than the sum of its proper divisors (14774415).

28531569 is a wasteful number, since it uses less digits than its factorization.

28531569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37628.

The product of its digits is 64800, while the sum is 39.

The square root of 28531569 is about 5341.4950154428. The cubic root of 28531569 is about 305.5684784299.

The spelling of 28531569 in words is "twenty-eight million, five hundred thirty-one thousand, five hundred sixty-nine".