81647095205 has 16 divisors (see below), whose sum is σ = 105525114240. Its totient is φ = 60286413888.

The previous prime is 81647095199. The next prime is 81647095249. The reversal of 81647095205 is 50259074618.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81647095205 - 2⁶ = 81647095141 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81647095205.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 548726 + ... + 681464.

It is an arithmetic number, because the mean of its divisors is an integer number (6595319640).

Almost surely, 2^81647095205 is an apocalyptic number.

It is an amenable number.

81647095205 is a deficient number, since it is larger than the sum of its proper divisors (23878019035).

81647095205 is a wasteful number, since it uses less digits than its factorization.

81647095205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142220.

The product of its (nonzero) digits is 604800, while the sum is 47.

The spelling of 81647095205 in words is "eighty-one billion, six hundred forty-seven million, ninety-five thousand, two hundred five".