28172825 has 24 divisors (see below), whose sum is σ = 37319040. Its totient is φ = 21024000.

The previous prime is 28172819. The next prime is 28172827. The reversal of 28172825 is 52827182.

It is not a de Polignac number, because 28172825 - 2¹⁸ = 27910681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28172827) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 63956 + ... + 64394.

It is an arithmetic number, because the mean of its divisors is an integer number (1554960).

Almost surely, 2^28172825 is an apocalyptic number.

28172825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28172825 is a deficient number, since it is larger than the sum of its proper divisors (9146215).

28172825 is a wasteful number, since it uses less digits than its factorization.

28172825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 617 (or 612 counting only the distinct ones).

The product of its digits is 17920, while the sum is 35.

The square root of 28172825 is about 5307.8079279492. The cubic root of 28172825 is about 304.2823762766.

The spelling of 28172825 in words is "twenty-eight million, one hundred seventy-two thousand, eight hundred twenty-five".