28131272 has 16 divisors (see below), whose sum is σ = 56803740. Its totient is φ = 12983616.

The previous prime is 28131253. The next prime is 28131283. The reversal of 28131272 is 27213182.

It can be written as a sum of positive squares in 2 ways, for example, as 24344356 + 3786916 = 4934^2 + 1946^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135143 + ... + 135350.

Almost surely, 2^28131272 is an apocalyptic number.

It is an amenable number.

28131272 is an abundant number, since it is smaller than the sum of its proper divisors (28672468).

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

28131272 is a wasteful number, since it uses less digits than its factorization.

28131272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270512 (or 270508 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 28131272 is about 5303.8921557664. The cubic root of 28131272 is about 304.1327040664.

The spelling of 28131272 in words is "twenty-eight million, one hundred thirty-one thousand, two hundred seventy-two".