81071832 has 16 divisors (see below), whose sum is σ = 202679640. Its totient is φ = 27023936.

The previous prime is 81071831. The next prime is 81071857. The reversal of 81071832 is 23817018.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81071832.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81071831) 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 3 ways as a sum of consecutive naturals, for example, 1688973 + ... + 1689020.

Almost surely, 2^81071832 is an apocalyptic number.

It is an amenable number.

81071832 is an abundant number, since it is smaller than the sum of its proper divisors (121607808).

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

81071832 is a wasteful number, since it uses less digits than its factorization.

81071832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3378002 (or 3377998 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 81071832 is about 9003.9897823132. The cubic root of 81071832 is about 432.8027341313.

The spelling of 81071832 in words is "eighty-one million, seventy-one thousand, eight hundred thirty-two".