81593472 has 128 divisors (see below), whose sum is σ = 237945600. Its totient is φ = 24657920.

The previous prime is 81593461. The next prime is 81593507. The reversal of 81593472 is 27439518.

It is a tau number, because it is divible by the number of its divisors (128).

It is a self number, because there is not a number n which added to its sum of digits gives 81593472.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 189097 + ... + 189527.

It is an arithmetic number, because the mean of its divisors is an integer number (1858950).

Almost surely, 2^81593472 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 81593472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118972800).

81593472 is an abundant number, since it is smaller than the sum of its proper divisors (156352128).

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

81593472 is a wasteful number, since it uses less digits than its factorization.

81593472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494 (or 482 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 81593472 is about 9032.9104944088. The cubic root of 81593472 is about 433.7290103262.

The spelling of 81593472 in words is "eighty-one million, five hundred ninety-three thousand, four hundred seventy-two".