165569965561 has 48 divisors (see below), whose sum is σ = 233572889088. Its totient is φ = 115249478400.

The previous prime is 165569965549. The next prime is 165569965609.

165569965561 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 165569965561 - 2¹⁵ = 165569932793 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165569965493 and 165569965502.

It is not an unprimeable number, because it can be changed into a prime (165569965061) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 163900 + ... + 598333.

It is an arithmetic number, because the mean of its divisors is an integer number (4866101856).

Almost surely, 2^165569965561 is an apocalyptic number.

165569965561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

165569965561 is a deficient number, since it is larger than the sum of its proper divisors (68002923527).

165569965561 is a wasteful number, since it uses less digits than its factorization.

165569965561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762302 (or 762295 counting only the distinct ones).

The product of its digits is 65610000, while the sum is 64.

The spelling of 165569965561 in words is "one hundred sixty-five billion, five hundred sixty-nine million, nine hundred sixty-five thousand, five hundred sixty-one".