81443132 has 12 divisors (see below), whose sum is σ = 142745736. Its totient is φ = 40658640.

The previous prime is 81443119. The next prime is 81443137. The reversal of 81443132 is 23134418.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81443137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12758 + ... + 18045.

It is an arithmetic number, because the mean of its divisors is an integer number (11895478).

Almost surely, 2^81443132 is an apocalyptic number.

It is an amenable number.

81443132 is a deficient number, since it is larger than the sum of its proper divisors (61302604).

81443132 is a wasteful number, since it uses less digits than its factorization.

81443132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31468 (or 31466 counting only the distinct ones).

The product of its digits is 2304, while the sum is 26.

The square root of 81443132 is about 9024.5848657985. The cubic root of 81443132 is about 433.4624575094.

The spelling of 81443132 in words is "eighty-one million, four hundred forty-three thousand, one hundred thirty-two".