165564455361 has 4 divisors (see below), whose sum is σ = 220752607152. Its totient is φ = 110376303572.

The previous prime is 165564455359. The next prime is 165564455369. The reversal of 165564455361 is 163554465561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 165564455361 - 2¹ = 165564455359 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165564455369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27594075891 + ... + 27594075896.

It is an arithmetic number, because the mean of its divisors is an integer number (55188151788).

Almost surely, 2^165564455361 is an apocalyptic number.

It is an amenable number.

165564455361 is a deficient number, since it is larger than the sum of its proper divisors (55188151791).

165564455361 is an equidigital number, since it uses as much as digits as its factorization.

165564455361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55188151790.

The product of its digits is 6480000, while the sum is 51.

The spelling of 165564455361 in words is "one hundred sixty-five billion, five hundred sixty-four million, four hundred fifty-five thousand, three hundred sixty-one".