165399643 has 2 divisors, whose sum is σ = 165399644. Its totient is φ = 165399642.

The previous prime is 165399631. The next prime is 165399653. The reversal of 165399643 is 346993561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165399643 - 2⁹ = 165399131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165399593 and 165399602.

It is not a weakly prime, because it can be changed into another prime (165399653) 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, 82699821 + 82699822.

It is an arithmetic number, because the mean of its divisors is an integer number (82699822).

Almost surely, 2^165399643 is an apocalyptic number.

165399643 is a deficient number, since it is larger than the sum of its proper divisors (1).

165399643 is an equidigital number, since it uses as much as digits as its factorization.

165399643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 524880, while the sum is 46.

The square root of 165399643 is about 12860.7792532179. The cubic root of 165399643 is about 548.9231193279.

The spelling of 165399643 in words is "one hundred sixty-five million, three hundred ninety-nine thousand, six hundred forty-three".