28170900 has 108 divisors (see below), whose sum is σ = 89403132. Its totient is φ = 7418880.

The previous prime is 28170889. The next prime is 28170913. The reversal of 28170900 is 907182.

It can be written as a sum of positive squares in 6 ways, for example, as 10227204 + 17943696 = 3198^2 + 4236^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 101562 + ... + 101838.

Almost surely, 2^28170900 is an apocalyptic number.

28170900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28170900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44701566).

28170900 is an abundant number, since it is smaller than the sum of its proper divisors (61232232).

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

28170900 is a wasteful number, since it uses less digits than its factorization.

28170900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 28170900 is about 5307.6265882219. The cubic root of 28170900 is about 304.2754457573.

The spelling of 28170900 in words is "twenty-eight million, one hundred seventy thousand, nine hundred".