81585710001 has 16 divisors (see below), whose sum is σ = 121014971520. Its totient is φ = 54324209520.

The previous prime is 81585709991. The next prime is 81585710027. The reversal of 81585710001 is 10001758518.

It is a happy number.

81585710001 is a `hidden beast` number, since 8 + 1 + 585 + 71 + 0 + 0 + 0 + 1 = 666.

It is not a de Polignac number, because 81585710001 - 2⁷ = 81585709873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81585710051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1818085 + ... + 1862418.

It is an arithmetic number, because the mean of its divisors is an integer number (7563435720).

Almost surely, 2^81585710001 is an apocalyptic number.

It is an amenable number.

81585710001 is a deficient number, since it is larger than the sum of its proper divisors (39429261519).

81585710001 is a wasteful number, since it uses less digits than its factorization.

81585710001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3681333 (or 3681327 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 36.

The spelling of 81585710001 in words is "eighty-one billion, five hundred eighty-five million, seven hundred ten thousand, one".