165041815 has 4 divisors (see below), whose sum is σ = 198050184. Its totient is φ = 132033448.

The previous prime is 165041803. The next prime is 165041819. The reversal of 165041815 is 518140561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 518140561 = 53 ⋅9776237.

It is a cyclic number.

It is not a de Polignac number, because 165041815 - 2¹¹ = 165039767 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165041819) 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, 16504177 + ... + 16504186.

It is an arithmetic number, because the mean of its divisors is an integer number (49512546).

Almost surely, 2^165041815 is an apocalyptic number.

165041815 is a deficient number, since it is larger than the sum of its proper divisors (33008369).

165041815 is an equidigital number, since it uses as much as digits as its factorization.

165041815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33008368.

The product of its (nonzero) digits is 4800, while the sum is 31.

The square root of 165041815 is about 12846.8601222244. The cubic root of 165041815 is about 548.5269840947.

The spelling of 165041815 in words is "one hundred sixty-five million, forty-one thousand, eight hundred fifteen".