28171325 has 72 divisors (see below), whose sum is σ = 46012680. Its totient is φ = 16934400.

The previous prime is 28171307. The next prime is 28171327. The reversal of 28171325 is 52317182.

It can be written as a sum of positive squares in 12 ways, for example, as 20448484 + 7722841 = 4522^2 + 2779^2 .

It is not a de Polignac number, because 28171325 - 2¹⁰ = 28170301 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28171327) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 461795 + ... + 461855.

It is an arithmetic number, because the mean of its divisors is an integer number (639065).

Almost surely, 2^28171325 is an apocalyptic number.

28171325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28171325 is a deficient number, since it is larger than the sum of its proper divisors (17841355).

28171325 is a wasteful number, since it uses less digits than its factorization.

28171325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 115 counting only the distinct ones).

The product of its digits is 3360, while the sum is 29.

The square root of 28171325 is about 5307.6666247985. Note that the first 4 decimals coincide. The cubic root of 28171325 is about 304.2769758991.

The spelling of 28171325 in words is "twenty-eight million, one hundred seventy-one thousand, three hundred twenty-five".