28172536 has 64 divisors (see below), whose sum is σ = 64774080. Its totient is φ = 11212800.

The previous prime is 28172513. The next prime is 28172549. The reversal of 28172536 is 63527182.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (34).

Its product of digits (20160) is a multiple of the sum of its prime divisors (420).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96006 + ... + 96298.

It is an arithmetic number, because the mean of its divisors is an integer number (1012095).

Almost surely, 2^28172536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28172536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32387040).

28172536 is an abundant number, since it is smaller than the sum of its proper divisors (36601544).

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

28172536 is a wasteful number, since it uses less digits than its factorization.

28172536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424 (or 420 counting only the distinct ones).

The product of its digits is 20160, while the sum is 34.

The square root of 28172536 is about 5307.7807038347. The cubic root of 28172536 is about 304.2813358187.

The spelling of 28172536 in words is "twenty-eight million, one hundred seventy-two thousand, five hundred thirty-six".