81432576 has 117 divisors (see below), whose sum is σ = 240332131. Its totient is φ = 26566656.

The previous prime is 81432553. The next prime is 81432577. The reversal of 81432576 is 67523418.

The square root of 81432576 is 9024.

It is a perfect power (a square), and thus also a powerful number.

81432576 is a `hidden beast` number, since 81 + 4 + 3 + 2 + 576 = 666.

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

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81432576.

It is not an unprimeable number, because it can be changed into a prime (81432577) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1732585 + ... + 1732631.

Almost surely, 2^81432576 is an apocalyptic number.

81432576 is the 9024-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81432576

81432576 is an abundant number, since it is smaller than the sum of its proper divisors (158899555).

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

81432576 is an equidigital number, since it uses as much as digits as its factorization.

81432576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 52 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The cubic root of 81432576 is about 433.4437294010.

Multiplying 81432576 by its sum of digits (36), we get a square (2931572736 = 54144²).

81432576 divided by its sum of digits (36) gives a square (2262016 = 1504²).

The spelling of 81432576 in words is "eighty-one million, four hundred thirty-two thousand, five hundred seventy-six".