66615116571 has 12 divisors (see below), whose sum is σ = 96327934872. Its totient is φ = 44361108576.

The previous prime is 66615116527. The next prime is 66615116587. The reversal of 66615116571 is 17561151666.

It is not a de Polignac number, because 66615116571 - 2¹¹ = 66615114523 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66615156571) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4072146 + ... + 4088471.

It is an arithmetic number, because the mean of its divisors is an integer number (8027327906).

Almost surely, 2^66615116571 is an apocalyptic number.

66615116571 is a deficient number, since it is larger than the sum of its proper divisors (29712818301).

66615116571 is a wasteful number, since it uses less digits than its factorization.

66615116571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8161530 (or 8161527 counting only the distinct ones).

The product of its digits is 226800, while the sum is 45.

The spelling of 66615116571 in words is "sixty-six billion, six hundred fifteen million, one hundred sixteen thousand, five hundred seventy-one".