166393858417 has 2 divisors, whose sum is σ = 166393858418. Its totient is φ = 166393858416.

The previous prime is 166393858403. The next prime is 166393858427. The reversal of 166393858417 is 714858393661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 96378581601 + 70015276816 = 310449^2 + 264604^2 .

It is a cyclic number.

It is not a de Polignac number, because 166393858417 - 2²⁷ = 166259640689 is a prime.

It is a super-2 number, since 2×166393858417² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166393858427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83196929208 + 83196929209.

It is an arithmetic number, because the mean of its divisors is an integer number (83196929209).

Almost surely, 2^166393858417 is an apocalyptic number.

It is an amenable number.

166393858417 is a deficient number, since it is larger than the sum of its proper divisors (1).

166393858417 is an equidigital number, since it uses as much as digits as its factorization.

166393858417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26127360, while the sum is 61.

The spelling of 166393858417 in words is "one hundred sixty-six billion, three hundred ninety-three million, eight hundred fifty-eight thousand, four hundred seventeen".