28186840 has 96 divisors (see below), whose sum is σ = 73126800. Its totient is φ = 9685760.

The previous prime is 28186813. The next prime is 28186849. The reversal of 28186840 is 4868182.

It is a self number, because there is not a number n which added to its sum of digits gives 28186840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28186849) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 599697 + ... + 599743.

Almost surely, 2^28186840 is an apocalyptic number.

28186840 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 28186840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36563400).

28186840 is an abundant number, since it is smaller than the sum of its proper divisors (44939960).

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

28186840 is a wasteful number, since it uses less digits than its factorization.

28186840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 37.

The square root of 28186840 is about 5309.1279886625. The cubic root of 28186840 is about 304.3328245430.

The spelling of 28186840 in words is "twenty-eight million, one hundred eighty-six thousand, eight hundred forty".