81380832 has 96 divisors (see below), whose sum is σ = 234047520. Its totient is φ = 24606720.

The previous prime is 81380807. The next prime is 81380833. The reversal of 81380832 is 23808318.

It is a tau number, because it is divible by the number of its divisors (96).

It is a junction number, because it is equal to n+sod(n) for n = 81380793 and 81380802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81380833) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 75594 + ... + 76662.

It is an arithmetic number, because the mean of its divisors is an integer number (2437995).

Almost surely, 2^81380832 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 81380832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117023760).

81380832 is an abundant number, since it is smaller than the sum of its proper divisors (152666688).

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

81380832 is a wasteful number, since it uses less digits than its factorization.

81380832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1156 (or 1148 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 81380832 is about 9021.1325231370. The cubic root of 81380832 is about 433.3519034777.

The spelling of 81380832 in words is "eighty-one million, three hundred eighty thousand, eight hundred thirty-two".