166813713617 has 2 divisors, whose sum is σ = 166813713618. Its totient is φ = 166813713616.

The previous prime is 166813713593. The next prime is 166813713643. The reversal of 166813713617 is 716317318661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 155804667841 + 11009045776 = 394721^2 + 104924^2 .

It is a cyclic number.

It is not a de Polignac number, because 166813713617 - 2⁶ = 166813713553 is a prime.

It is not a weakly prime, because it can be changed into another prime (166813713317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83406856808 + 83406856809.

It is an arithmetic number, because the mean of its divisors is an integer number (83406856809).

Almost surely, 2^166813713617 is an apocalyptic number.

It is an amenable number.

166813713617 is a deficient number, since it is larger than the sum of its proper divisors (1).

166813713617 is an equidigital number, since it uses as much as digits as its factorization.

166813713617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 762048, while the sum is 50.

The spelling of 166813713617 in words is "one hundred sixty-six billion, eight hundred thirteen million, seven hundred thirteen thousand, six hundred seventeen".