165355276321 has 9 divisors (see below), whose sum is σ = 166303656883. Its totient is φ = 164412280480.

The previous prime is 165355276271. The next prime is 165355276327. The reversal of 165355276321 is 123672553561.

The square root of 165355276321 is 406639.

It is a perfect power (a square), and thus also a powerful number.

165355276321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 41845202721 + 123510073600 = 204561^2 + 351440^2 .

It is not a de Polignac number, because 165355276321 - 2³¹ = 163207792673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165355276327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 77666985 + ... + 77669113.

Almost surely, 2^165355276321 is an apocalyptic number.

165355276321 is the 406639-th square number.

165355276321 is the 203320-th centered octagonal number.

It is an amenable number.

165355276321 is a deficient number, since it is larger than the sum of its proper divisors (948380562).

165355276321 is an frugal number, since it uses more digits than its factorization.

165355276321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4640 (or 2320 counting only the distinct ones).

The product of its digits is 1134000, while the sum is 46.

The spelling of 165355276321 in words is "one hundred sixty-five billion, three hundred fifty-five million, two hundred seventy-six thousand, three hundred twenty-one".