71661016617 has 4 divisors (see below), whose sum is σ = 95548022160. Its totient is φ = 47774011076.

The previous prime is 71661016613. The next prime is 71661016633.

71661016617 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71661016617 - 2² = 71661016613 is a prime.

It is not an unprimeable number, because it can be changed into a prime (71661016613) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 11943502767 + ... + 11943502772.

It is an arithmetic number, because the mean of its divisors is an integer number (23887005540).

Almost surely, 2^71661016617 is an apocalyptic number.

It is an amenable number.

71661016617 is a deficient number, since it is larger than the sum of its proper divisors (23887005543).

71661016617 is a wasteful number, since it uses less digits than its factorization.

71661016617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23887005542.

The product of its (nonzero) digits is 63504, while the sum is 42.

The spelling of 71661016617 in words is "seventy-one billion, six hundred sixty-one million, sixteen thousand, six hundred seventeen".