81038724 has 72 divisors (see below), whose sum is σ = 215066880. Its totient is φ = 23606208.

The previous prime is 81038723. The next prime is 81038767. The reversal of 81038724 is 42783018.

81038724 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

81038724 is strictly pandigital in base 9.

It is not an unprimeable number, because it can be changed into a prime (81038723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55597 + ... + 57035.

It is an arithmetic number, because the mean of its divisors is an integer number (2987040).

Almost surely, 2^81038724 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 81038724, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107533440).

81038724 is an abundant number, since it is smaller than the sum of its proper divisors (134028156).

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

81038724 is a wasteful number, since it uses less digits than its factorization.

81038724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497 (or 1476 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 81038724 is about 9002.1510762706. The cubic root of 81038724 is about 432.7438103202.

The spelling of 81038724 in words is "eighty-one million, thirty-eight thousand, seven hundred twenty-four".