71512717665 has 32 divisors (see below), whose sum is σ = 116157580416. Its totient is φ = 37561328640.

The previous prime is 71512717621. The next prime is 71512717673. The reversal of 71512717665 is 56671721517.

It is not a de Polignac number, because 71512717665 - 2⁷ = 71512717537 is a prime.

It is a super-2 number, since 2×71512717665² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5835945 + ... + 5848185.

It is an arithmetic number, because the mean of its divisors is an integer number (3629924388).

Almost surely, 2^71512717665 is an apocalyptic number.

It is an amenable number.

71512717665 is a deficient number, since it is larger than the sum of its proper divisors (44644862751).

71512717665 is a wasteful number, since it uses less digits than its factorization.

71512717665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18129.

The product of its digits is 617400, while the sum is 48.

The spelling of 71512717665 in words is "seventy-one billion, five hundred twelve million, seven hundred seventeen thousand, six hundred sixty-five".