81032730 has 16 divisors (see below), whose sum is σ = 194478624. Its totient is φ = 21608720.

The previous prime is 81032723. The next prime is 81032759. The reversal of 81032730 is 3723018.

It is a self number, because there is not a number n which added to its sum of digits gives 81032730.

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 7 ways as a sum of consecutive naturals, for example, 1350516 + ... + 1350575.

It is an arithmetic number, because the mean of its divisors is an integer number (12154914).

Almost surely, 2^81032730 is an apocalyptic number.

81032730 is an abundant number, since it is smaller than the sum of its proper divisors (113445894).

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

81032730 is a wasteful number, since it uses less digits than its factorization.

81032730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2701101.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 81032730 is about 9001.8181496851. The cubic root of 81032730 is about 432.7331408105.

Adding to 81032730 its reverse (3723018), we get a palindrome (84755748).

The spelling of 81032730 in words is "eighty-one million, thirty-two thousand, seven hundred thirty".