165945599 has 2 divisors, whose sum is σ = 165945600. Its totient is φ = 165945598.

The previous prime is 165945589. The next prime is 165945607. The reversal of 165945599 is 995549561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165945599 - 2⁸ = 165945343 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165945599.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165945509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82972799 + 82972800.

It is an arithmetic number, because the mean of its divisors is an integer number (82972800).

Almost surely, 2^165945599 is an apocalyptic number.

165945599 is a deficient number, since it is larger than the sum of its proper divisors (1).

165945599 is an equidigital number, since it uses as much as digits as its factorization.

165945599 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2187000, while the sum is 53.

The square root of 165945599 is about 12881.9873854930. The cubic root of 165945599 is about 549.5264231983.

The spelling of 165945599 in words is "one hundred sixty-five million, nine hundred forty-five thousand, five hundred ninety-nine".