81647125582 has 64 divisors (see below), whose sum is σ = 136768927680. Its totient is φ = 36246528000.

The previous prime is 81647125541. The next prime is 81647125589. The reversal of 81647125582 is 28552174618.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81647125589) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 67088238 + ... + 67089454.

It is an arithmetic number, because the mean of its divisors is an integer number (2137014495).

Almost surely, 2^81647125582 is an apocalyptic number.

81647125582 is a deficient number, since it is larger than the sum of its proper divisors (55121802098).

81647125582 is a wasteful number, since it uses less digits than its factorization.

81647125582 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1717.

The product of its digits is 1075200, while the sum is 49.

The spelling of 81647125582 in words is "eighty-one billion, six hundred forty-seven million, one hundred twenty-five thousand, five hundred eighty-two".