165618013 has 4 divisors (see below), whose sum is σ = 180674208. Its totient is φ = 150561820.

The previous prime is 165618007. The next prime is 165618017. The reversal of 165618013 is 310816561.

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 165618013 - 2⁵ = 165617981 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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (165618017) 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, 7528081 + ... + 7528102.

It is an arithmetic number, because the mean of its divisors is an integer number (45168552).

Almost surely, 2^165618013 is an apocalyptic number.

It is an amenable number.

165618013 is a deficient number, since it is larger than the sum of its proper divisors (15056195).

165618013 is a wasteful number, since it uses less digits than its factorization.

165618013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15056194.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 165618013 is about 12869.2662183980. The cubic root of 165618013 is about 549.1645862495.

The spelling of 165618013 in words is "one hundred sixty-five million, six hundred eighteen thousand, thirteen".