81113144 has 16 divisors (see below), whose sum is σ = 173814000. Its totient is φ = 34762752.

The previous prime is 81113119. The next prime is 81113183. The reversal of 81113144 is 44131118.

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 3 ways as a sum of consecutive naturals, for example, 724169 + ... + 724280.

It is an arithmetic number, because the mean of its divisors is an integer number (10863375).

Almost surely, 2^81113144 is an apocalyptic number.

It is an amenable number.

81113144 is an abundant number, since it is smaller than the sum of its proper divisors (92700856).

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

81113144 is a wasteful number, since it uses less digits than its factorization.

81113144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1448462 (or 1448458 counting only the distinct ones).

The product of its digits is 384, while the sum is 23.

The square root of 81113144 is about 9006.2835842538. The cubic root of 81113144 is about 432.8762364807.

The spelling of 81113144 in words is "eighty-one million, one hundred thirteen thousand, one hundred forty-four".