165368639 has 12 divisors (see below), whose sum is σ = 178513776. Its totient is φ = 152660352.

The previous prime is 165368633. The next prime is 165368653. The reversal of 165368639 is 936863561.

It is a de Polignac number, because none of the positive numbers 2^k-165368639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165368593 and 165368602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165368633) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 46022 + ... + 49484.

It is an arithmetic number, because the mean of its divisors is an integer number (14876148).

Almost surely, 2^165368639 is an apocalyptic number.

165368639 is a deficient number, since it is larger than the sum of its proper divisors (13145137).

165368639 is an equidigital number, since it uses as much as digits as its factorization.

165368639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3586 (or 3533 counting only the distinct ones).

The product of its digits is 699840, while the sum is 47.

The square root of 165368639 is about 12859.5738265310. The cubic root of 165368639 is about 548.8888188188. Note that the first 4 decimals are identical.

The spelling of 165368639 in words is "one hundred sixty-five million, three hundred sixty-eight thousand, six hundred thirty-nine".