1665164173 has 2 divisors, whose sum is σ = 1665164174. Its totient is φ = 1665164172.

The previous prime is 1665164159. The next prime is 1665164191. The reversal of 1665164173 is 3714615661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1613869929 + 51294244 = 40173^2 + 7162^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1665164173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665164113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832582086 + 832582087.

It is an arithmetic number, because the mean of its divisors is an integer number (832582087).

Almost surely, 2^1665164173 is an apocalyptic number.

It is an amenable number.

1665164173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665164173 is an equidigital number, since it uses as much as digits as its factorization.

1665164173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 1665164173 is about 40806.4231831216. The cubic root of 1665164173 is about 1185.2747137370.

The spelling of 1665164173 in words is "one billion, six hundred sixty-five million, one hundred sixty-four thousand, one hundred seventy-three".