81594872 has 8 divisors (see below), whose sum is σ = 152990400. Its totient is φ = 40797432.

The previous prime is 81594847. The next prime is 81594889. The reversal of 81594872 is 27849518.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5099672 + ... + 5099687.

It is an arithmetic number, because the mean of its divisors is an integer number (19123800).

Almost surely, 2^81594872 is an apocalyptic number.

It is an amenable number.

81594872 is a deficient number, since it is larger than the sum of its proper divisors (71395528).

81594872 is a wasteful number, since it uses less digits than its factorization.

81594872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10199365 (or 10199361 counting only the distinct ones).

The product of its digits is 161280, while the sum is 44.

The square root of 81594872 is about 9032.9879884787. The cubic root of 81594872 is about 433.7314909868.

It can be divided in two parts, 8159 and 4872, that added together give a palindrome (13031).

The spelling of 81594872 in words is "eighty-one million, five hundred ninety-four thousand, eight hundred seventy-two".