165216643 has 2 divisors, whose sum is σ = 165216644. Its totient is φ = 165216642.

The previous prime is 165216631. The next prime is 165216679. The reversal of 165216643 is 346612561.

It is a weak prime.

It is an emirp because it is prime and its reverse (346612561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165216643 - 2⁹ = 165216131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165216599 and 165216608.

It is not a weakly prime, because it can be changed into another prime (165216043) 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, 82608321 + 82608322.

It is an arithmetic number, because the mean of its divisors is an integer number (82608322).

Almost surely, 2^165216643 is an apocalyptic number.

165216643 is a deficient number, since it is larger than the sum of its proper divisors (1).

165216643 is an equidigital number, since it uses as much as digits as its factorization.

165216643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 34.

The square root of 165216643 is about 12853.6626297721. The cubic root of 165216643 is about 548.7205997432.

The spelling of 165216643 in words is "one hundred sixty-five million, two hundred sixteen thousand, six hundred forty-three".