28531329 has 12 divisors (see below), whose sum is σ = 39103344. Its totient is φ = 18504144.

The previous prime is 28531297. The next prime is 28531337. The reversal of 28531329 is 92313582.

It is not a de Polignac number, because 28531329 - 2⁵ = 28531297 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28531329.

It is not an unprimeable number, because it can be changed into a prime (28531379) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 634 + ... + 7580.

It is an arithmetic number, because the mean of its divisors is an integer number (3258612).

Almost surely, 2^28531329 is an apocalyptic number.

It is an amenable number.

28531329 is a deficient number, since it is larger than the sum of its proper divisors (10572015).

28531329 is an equidigital number, since it uses as much as digits as its factorization.

28531329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7024 (or 6987 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 28531329 is about 5341.4725497750. The cubic root of 28531329 is about 305.5676216404.

The spelling of 28531329 in words is "twenty-eight million, five hundred thirty-one thousand, three hundred twenty-nine".