71660216545 has 4 divisors (see below), whose sum is σ = 85992259860. Its totient is φ = 57328173232.

The previous prime is 71660216527. The next prime is 71660216591. The reversal of 71660216545 is 54561206617.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31014027664 + 40646188881 = 176108^2 + 201609^2 .

It is a cyclic number.

It is not a de Polignac number, because 71660216545 - 2¹⁹ = 71659692257 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7166021650 + ... + 7166021659.

It is an arithmetic number, because the mean of its divisors is an integer number (21498064965).

Almost surely, 2^71660216545 is an apocalyptic number.

It is an amenable number.

71660216545 is a deficient number, since it is larger than the sum of its proper divisors (14332043315).

71660216545 is a wasteful number, since it uses less digits than its factorization.

71660216545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14332043314.

The product of its (nonzero) digits is 302400, while the sum is 43.

The spelling of 71660216545 in words is "seventy-one billion, six hundred sixty million, two hundred sixteen thousand, five hundred forty-five".