28162720 has 24 divisors (see below), whose sum is σ = 66534804. Its totient is φ = 11265024.

The previous prime is 28162711. The next prime is 28162751. The reversal of 28162720 is 2726182.

It can be written as a sum of positive squares in 2 ways, for example, as 27920656 + 242064 = 5284^2 + 492^2 .

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 3 ways as a sum of consecutive naturals, for example, 87849 + ... + 88168.

Almost surely, 2^28162720 is an apocalyptic number.

28162720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28162720 is an abundant number, since it is smaller than the sum of its proper divisors (38372084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28162720 is a wasteful number, since it uses less digits than its factorization.

28162720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176032 (or 176024 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 28162720 is about 5306.8559430231. The cubic root of 28162720 is about 304.2459920292.

It can be divided in two parts, 28162 and 720, that added together give a palindrome (28882).

The spelling of 28162720 in words is "twenty-eight million, one hundred sixty-two thousand, seven hundred twenty".