165766399 has 2 divisors, whose sum is σ = 165766400. Its totient is φ = 165766398.

The previous prime is 165766379. The next prime is 165766423. The reversal of 165766399 is 993667561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 165766399 - 2¹³ = 165758207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165766309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82883199 + 82883200.

It is an arithmetic number, because the mean of its divisors is an integer number (82883200).

Almost surely, 2^165766399 is an apocalyptic number.

165766399 is a deficient number, since it is larger than the sum of its proper divisors (1).

165766399 is an equidigital number, since it uses as much as digits as its factorization.

165766399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1837080, while the sum is 52.

The square root of 165766399 is about 12875.0300582173. The cubic root of 165766399 is about 549.3285458944.

The spelling of 165766399 in words is "one hundred sixty-five million, seven hundred sixty-six thousand, three hundred ninety-nine".