81090828 has 192 divisors, whose sum is σ = 266936320. Its totient is φ = 20715264.

The previous prime is 81090817. The next prime is 81090829. The reversal of 81090828 is 82809018.

81090828 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

81090828 is strictly pandigital in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 81090792 and 81090801.

It is not an unprimeable number, because it can be changed into a prime (81090829) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 363525 + ... + 363747.

Almost surely, 2^81090828 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 81090828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133468160).

81090828 is an abundant number, since it is smaller than the sum of its proper divisors (185845492).

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

81090828 is a wasteful number, since it uses less digits than its factorization.

81090828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293 (or 285 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 81090828 is about 9005.0445862305. The cubic root of 81090828 is about 432.8365349327.

It can be divided in two parts, 81090 and 828, that added together give a palindrome (81918).

The spelling of 81090828 in words is "eighty-one million, ninety thousand, eight hundred twenty-eight".