81975528 has 48 divisors (see below), whose sum is σ = 223641600. Its totient is φ = 27125280.

The previous prime is 81975503. The next prime is 81975533. The reversal of 81975528 is 82557918.

It is a happy number.

81975528 is a `hidden beast` number, since 8 + 1 + 97 + 552 + 8 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5913 + ... + 14103.

It is an arithmetic number, because the mean of its divisors is an integer number (4659200).

Almost surely, 2^81975528 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 81975528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111820800).

81975528 is an abundant number, since it is smaller than the sum of its proper divisors (141666072).

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

81975528 is a wasteful number, since it uses less digits than its factorization.

81975528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8342 (or 8335 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The square root of 81975528 is about 9054.0337971536. The cubic root of 81975528 is about 434.4049255162.

Adding to 81975528 its product of digits (201600), we get a palindrome (82177128).

The spelling of 81975528 in words is "eighty-one million, nine hundred seventy-five thousand, five hundred twenty-eight".