82189728 has 120 divisors (see below), whose sum is σ = 248540292. Its totient is φ = 26625024.

The previous prime is 82189721. The next prime is 82189817. The reversal of 82189728 is 82798128.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 64448784 + 17740944 = 8028^2 + 4212^2 .

It is not an unprimeable number, because it can be changed into a prime (82189721) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 95476 + ... + 96332.

Almost surely, 2^82189728 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 82189728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124270146).

82189728 is an abundant number, since it is smaller than the sum of its proper divisors (166350564).

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

82189728 is a wasteful number, since it uses less digits than its factorization.

82189728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 916 (or 899 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The square root of 82189728 is about 9065.8550617137. The cubic root of 82189728 is about 434.7829595035.

Subtracting 82189728 from its reverse (82798128), we obtain a square (608400 = 780²).

The spelling of 82189728 in words is "eighty-two million, one hundred eighty-nine thousand, seven hundred twenty-eight".