28156385 has 16 divisors (see below), whose sum is σ = 35717760. Its totient is φ = 21248640.

The previous prime is 28156363. The next prime is 28156417. The reversal of 28156385 is 58365182.

It is not a de Polignac number, because 28156385 - 2⁶ = 28156321 is a prime.

It is a plaindrome in base 13.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 29069 + ... + 30021.

It is an arithmetic number, because the mean of its divisors is an integer number (2232360).

Almost surely, 2^28156385 is an apocalyptic number.

It is an amenable number.

28156385 is a deficient number, since it is larger than the sum of its proper divisors (7561375).

28156385 is a wasteful number, since it uses less digits than its factorization.

28156385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1288.

The product of its digits is 57600, while the sum is 38.

The square root of 28156385 is about 5306.2590400394. The cubic root of 28156385 is about 304.2231776739.

The spelling of 28156385 in words is "twenty-eight million, one hundred fifty-six thousand, three hundred eighty-five".