28168686 has 96 divisors (see below), whose sum is σ = 77837760. Its totient is φ = 7160832.

The previous prime is 28168669. The next prime is 28168687. The reversal of 28168686 is 68686182.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28168687) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 47206 + ... + 47798.

It is an arithmetic number, because the mean of its divisors is an integer number (810810).

Almost surely, 2^28168686 is an apocalyptic number.

28168686 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 28168686, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38918880).

28168686 is an abundant number, since it is smaller than the sum of its proper divisors (49669074).

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

28168686 is a wasteful number, since it uses less digits than its factorization.

28168686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650 (or 647 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 28168686 is about 5307.4180163239. The cubic root of 28168686 is about 304.2674743698.

The spelling of 28168686 in words is "twenty-eight million, one hundred sixty-eight thousand, six hundred eighty-six".