81084585 has 16 divisors (see below), whose sum is σ = 131935680. Its totient is φ = 42511680.

The previous prime is 81084569. The next prime is 81084589. The reversal of 81084585 is 58548018.

It is not a de Polignac number, because 81084585 - 2⁴ = 81084569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81084589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44926 + ... + 46695.

It is an arithmetic number, because the mean of its divisors is an integer number (8245980).

Almost surely, 2^81084585 is an apocalyptic number.

It is an amenable number.

81084585 is a deficient number, since it is larger than the sum of its proper divisors (50851095).

81084585 is a wasteful number, since it uses less digits than its factorization.

81084585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91688.

The product of its (nonzero) digits is 51200, while the sum is 39.

The square root of 81084585 is about 9004.6979405197. The cubic root of 81084585 is about 432.8254269447.

The spelling of 81084585 in words is "eighty-one million, eighty-four thousand, five hundred eighty-five".