28131472 has 20 divisors (see below), whose sum is σ = 54707436. Its totient is φ = 14013440.

The previous prime is 28131449. The next prime is 28131473. The reversal of 28131472 is 27413182.

It can be written as a sum of positive squares in 2 ways, for example, as 24760576 + 3370896 = 4976^2 + 1836^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 28131472.

It is not an unprimeable number, because it can be changed into a prime (28131473) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1368 + ... + 7624.

Almost surely, 2^28131472 is an apocalyptic number.

It is an amenable number.

28131472 is a deficient number, since it is larger than the sum of its proper divisors (26575964).

28131472 is a wasteful number, since it uses less digits than its factorization.

28131472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6546 (or 6540 counting only the distinct ones).

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

The square root of 28131472 is about 5303.9110098115. The cubic root of 28131472 is about 304.1334248111.

The spelling of 28131472 in words is "twenty-eight million, one hundred thirty-one thousand, four hundred seventy-two".