81459744 has 96 divisors (see below), whose sum is σ = 226437120. Its totient is φ = 25588992.

The previous prime is 81459737. The next prime is 81459773. The reversal of 81459744 is 44795418.

It is a tau number, because it is divible by the number of its divisors (96).

It is a junction number, because it is equal to n+sod(n) for n = 81459696 and 81459705.

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 15 ways as a sum of consecutive naturals, for example, 174199 + ... + 174665.

It is an arithmetic number, because the mean of its divisors is an integer number (2358720).

Almost surely, 2^81459744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81459744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113218560).

81459744 is an abundant number, since it is smaller than the sum of its proper divisors (144977376).

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

81459744 is a wasteful number, since it uses less digits than its factorization.

81459744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582 (or 574 counting only the distinct ones).

The product of its digits is 161280, while the sum is 42.

The square root of 81459744 is about 9025.5051936166. The cubic root of 81459744 is about 433.4919266971.

The spelling of 81459744 in words is "eighty-one million, four hundred fifty-nine thousand, seven hundred forty-four".