166890157793 has 2 divisors, whose sum is σ = 166890157794. Its totient is φ = 166890157792.

The previous prime is 166890157769. The next prime is 166890157829. The reversal of 166890157793 is 397751098661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125814218209 + 41075939584 = 354703^2 + 202672^2 .

It is a cyclic number.

It is not a de Polignac number, because 166890157793 - 2⁶ = 166890157729 is a prime.

It is not a weakly prime, because it can be changed into another prime (166890157703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83445078896 + 83445078897.

It is an arithmetic number, because the mean of its divisors is an integer number (83445078897).

Almost surely, 2^166890157793 is an apocalyptic number.

It is an amenable number.

166890157793 is a deficient number, since it is larger than the sum of its proper divisors (1).

166890157793 is an equidigital number, since it uses as much as digits as its factorization.

166890157793 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17146080, while the sum is 62.

The spelling of 166890157793 in words is "one hundred sixty-six billion, eight hundred ninety million, one hundred fifty-seven thousand, seven hundred ninety-three".