13166208065691 has 72 divisors (see below), whose sum is σ = 19978188516000. Its totient is φ = 8345578832640.

The previous prime is 13166208065687. The next prime is 13166208065719. The reversal of 13166208065691 is 19656080266131.

13166208065691 is a `hidden beast` number, since 1 + 3 + 1 + 6 + 620 + 8 + 0 + 6 + 5 + 6 + 9 + 1 = 666.

It is not a de Polignac number, because 13166208065691 - 2² = 13166208065687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13166208065651) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1209123775 + ... + 1209134663.

It is an arithmetic number, because the mean of its divisors is an integer number (277474840500).

Almost surely, 2^{13166208065691} is an apocalyptic number.

13166208065691 is a deficient number, since it is larger than the sum of its proper divisors (6811980450309).

13166208065691 is a wasteful number, since it uses less digits than its factorization.

13166208065691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11985 (or 11911 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 13166208065691 in words is "thirteen trillion, one hundred sixty-six billion, two hundred eight million, sixty-five thousand, six hundred ninety-one".