28291172 has 24 divisors (see below), whose sum is σ = 60935616. Its totient is φ = 11191968.

The previous prime is 28291169. The next prime is 28291181. The reversal of 28291172 is 27119282.

It is a happy number.

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 7 ways as a sum of consecutive naturals, for example, 38498 + ... + 39225.

It is an arithmetic number, because the mean of its divisors is an integer number (2538984).

Almost surely, 2^28291172 is an apocalyptic number.

It is an amenable number.

28291172 is an abundant number, since it is smaller than the sum of its proper divisors (32644444).

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

28291172 is a wasteful number, since it uses less digits than its factorization.

28291172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77747 (or 77745 counting only the distinct ones).

The product of its digits is 4032, while the sum is 32.

The square root of 28291172 is about 5318.9446321615. The cubic root of 28291172 is about 304.7078524752.

The spelling of 28291172 in words is "twenty-eight million, two hundred ninety-one thousand, one hundred seventy-two".