165645041 has 4 divisors (see below), whose sum is σ = 170121972. Its totient is φ = 161168112.

The previous prime is 165644993. The next prime is 165645047. The reversal of 165645041 is 140546561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 90649441 + 74995600 = 9521^2 + 8660^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165645041 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165644989 and 165645007.

It is not an unprimeable number, because it can be changed into a prime (165645047) 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 3 ways as a sum of consecutive naturals, for example, 2238410 + ... + 2238483.

It is an arithmetic number, because the mean of its divisors is an integer number (42530493).

Almost surely, 2^165645041 is an apocalyptic number.

It is an amenable number.

165645041 is a deficient number, since it is larger than the sum of its proper divisors (4476931).

165645041 is an equidigital number, since it uses as much as digits as its factorization.

165645041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4476930.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 165645041 is about 12870.3162742801. The cubic root of 165645041 is about 549.1944582278.

The spelling of 165645041 in words is "one hundred sixty-five million, six hundred forty-five thousand, forty-one".