28156329 has 10 divisors (see below), whose sum is σ = 42060810. Its totient is φ = 18770832.

The previous prime is 28156321. The next prime is 28156333. The reversal of 28156329 is 92365182.

28156329 is a `hidden beast` number, since 2 + 8 + 15 + 632 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 24235929 + 3920400 = 4923^2 + 1980^2 .

It is not a de Polignac number, because 28156329 - 2³ = 28156321 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28156293 and 28156302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28156321) 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 9 ways as a sum of consecutive naturals, for example, 173724 + ... + 173885.

It is an arithmetic number, because the mean of its divisors is an integer number (4206081).

Almost surely, 2^28156329 is an apocalyptic number.

It is an amenable number.

28156329 is a deficient number, since it is larger than the sum of its proper divisors (13904481).

28156329 is an equidigital number, since it uses as much as digits as its factorization.

28156329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347621 (or 347612 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 28156329 is about 5306.2537632495. The cubic root of 28156329 is about 304.2229759848. Note that the first 3 decimals are identical.

The spelling of 28156329 in words is "twenty-eight million, one hundred fifty-six thousand, three hundred twenty-nine".