71918965661 has 8 divisors (see below), whose sum is σ = 75722210880. Its totient is φ = 68117524128.

The previous prime is 71918965639. The next prime is 71918965693. The reversal of 71918965661 is 16656981917.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71918965661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71918965661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71918961661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 368681 + ... + 528926.

It is an arithmetic number, because the mean of its divisors is an integer number (9465276360).

Almost surely, 2^71918965661 is an apocalyptic number.

It is an amenable number.

71918965661 is a deficient number, since it is larger than the sum of its proper divisors (3803245219).

71918965661 is a wasteful number, since it uses less digits than its factorization.

71918965661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901843.

The product of its digits is 4898880, while the sum is 59.

The spelling of 71918965661 in words is "seventy-one billion, nine hundred eighteen million, nine hundred sixty-five thousand, six hundred sixty-one".