165844643 has 2 divisors, whose sum is σ = 165844644. Its totient is φ = 165844642.

The previous prime is 165844607. The next prime is 165844661. The reversal of 165844643 is 346448561.

It is a happy number.

165844643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (346448561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165844643 - 2⁸ = 165844387 is a prime.

It is a super-2 number, since 2×165844643² = 55008891223594898, which contains 22 as substring.

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 165844643.

It is not a weakly prime, because it can be changed into another prime (165844603) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82922321 + 82922322.

It is an arithmetic number, because the mean of its divisors is an integer number (82922322).

Almost surely, 2^165844643 is an apocalyptic number.

165844643 is a deficient number, since it is larger than the sum of its proper divisors (1).

165844643 is an equidigital number, since it uses as much as digits as its factorization.

165844643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 276480, while the sum is 41.

The square root of 165844643 is about 12878.0682945852. The cubic root of 165844643 is about 549.4149624866.

The spelling of 165844643 in words is "one hundred sixty-five million, eight hundred forty-four thousand, six hundred forty-three".