165645546561 has 64 divisors (see below), whose sum is σ = 269879869440. Its totient is φ = 99580000320.

The previous prime is 165645546541. The next prime is 165645546581.

165645546561 is a `hidden beast` number, since 1 + 6 + 5 + 6 + 45 + 546 + 56 + 1 = 666.

165645546561 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (165645546541) and next prime (165645546581).

It is not a de Polignac number, because 165645546561 - 2¹⁷ = 165645415489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165645546498 and 165645546507.

It is not an unprimeable number, because it can be changed into a prime (165645546541) 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 in 63 ways as a sum of consecutive naturals, for example, 26961856 + ... + 26967998.

It is an arithmetic number, because the mean of its divisors is an integer number (4216872960).

Almost surely, 2^165645546561 is an apocalyptic number.

165645546561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

165645546561 is a deficient number, since it is larger than the sum of its proper divisors (104234322879).

165645546561 is a wasteful number, since it uses less digits than its factorization.

165645546561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6883 (or 6877 counting only the distinct ones).

The product of its digits is 12960000, while the sum is 54.

The spelling of 165645546561 in words is "one hundred sixty-five billion, six hundred forty-five million, five hundred forty-six thousand, five hundred sixty-one".