66217761713 has 2 divisors, whose sum is σ = 66217761714. Its totient is φ = 66217761712.

The previous prime is 66217761661. The next prime is 66217761733. The reversal of 66217761713 is 31716771266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63580631104 + 2637130609 = 252152^2 + 51353^2 .

It is a cyclic number.

It is not a de Polignac number, because 66217761713 - 2¹⁶ = 66217696177 is a prime.

It is not a weakly prime, because it can be changed into another prime (66217761733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33108880856 + 33108880857.

It is an arithmetic number, because the mean of its divisors is an integer number (33108880857).

Almost surely, 2^66217761713 is an apocalyptic number.

It is an amenable number.

66217761713 is a deficient number, since it is larger than the sum of its proper divisors (1).

66217761713 is an equidigital number, since it uses as much as digits as its factorization.

66217761713 is an evil number, because the sum of its binary digits is even.

The product of its digits is 444528, while the sum is 47.

The spelling of 66217761713 in words is "sixty-six billion, two hundred seventeen million, seven hundred sixty-one thousand, seven hundred thirteen".