2166643793 has 2 divisors, whose sum is σ = 2166643794. Its totient is φ = 2166643792.

The previous prime is 2166643751. The next prime is 2166643799. The reversal of 2166643793 is 3973466612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1857868609 + 308775184 = 43103^2 + 17572^2 .

It is a cyclic number.

It is not a de Polignac number, because 2166643793 - 2¹⁰ = 2166642769 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2166643799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1083321896 + 1083321897.

It is an arithmetic number, because the mean of its divisors is an integer number (1083321897).

Almost surely, 2^2166643793 is an apocalyptic number.

It is an amenable number.

2166643793 is a deficient number, since it is larger than the sum of its proper divisors (1).

2166643793 is an equidigital number, since it uses as much as digits as its factorization.

2166643793 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 47.

The square root of 2166643793 is about 46547.2211093208. The cubic root of 2166643793 is about 1293.9847925117.

The spelling of 2166643793 in words is "two billion, one hundred sixty-six million, six hundred forty-three thousand, seven hundred ninety-three".