28565531 has 8 divisors (see below), whose sum is σ = 30451200. Its totient is φ = 26718120.

The previous prime is 28565513. The next prime is 28565533. The reversal of 28565531 is 13556582.

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

It is a cyclic number.

It is not a de Polignac number, because 28565531 - 2²² = 24371227 is a prime.

It is a super-2 number, since 2×28565531² = 1631979122623922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28565491 and 28565500.

It is not an unprimeable number, because it can be changed into a prime (28565533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8015 + ... + 11016.

It is an arithmetic number, because the mean of its divisors is an integer number (3806400).

Almost surely, 2^28565531 is an apocalyptic number.

28565531 is a deficient number, since it is larger than the sum of its proper divisors (1885669).

28565531 is a wasteful number, since it uses less digits than its factorization.

28565531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19129.

The product of its digits is 36000, while the sum is 35.

The square root of 28565531 is about 5344.6731424850. The cubic root of 28565531 is about 305.6896728601.

The spelling of 28565531 in words is "twenty-eight million, five hundred sixty-five thousand, five hundred thirty-one".