81444084 has 24 divisors (see below), whose sum is σ = 191536128. Its totient is φ = 26933760.

The previous prime is 81444049. The next prime is 81444109. The reversal of 81444084 is 48044418.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25197 + ... + 28244.

It is an arithmetic number, because the mean of its divisors is an integer number (7980672).

Almost surely, 2^81444084 is an apocalyptic number.

It is an amenable number.

81444084 is an abundant number, since it is smaller than the sum of its proper divisors (110092044).

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

81444084 is a wasteful number, since it uses less digits than its factorization.

81444084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53575 (or 53573 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 33.

The square root of 81444084 is about 9024.6376104528. The cubic root of 81444084 is about 433.4641464369.

The spelling of 81444084 in words is "eighty-one million, four hundred forty-four thousand, eighty-four".