165617865 has 56 divisors (see below), whose sum is σ = 340596288. Its totient is φ = 75699360.

The previous prime is 165617861. The next prime is 165617873. The reversal of 165617865 is 568716561.

165617865 is a `hidden beast` number, since 1 + 6 + 561 + 7 + 86 + 5 = 666.

165617865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165617865 - 2² = 165617861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 165617865.

It is not an unprimeable number, because it can be changed into a prime (165617861) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 22270 + ... + 28760.

Almost surely, 2^165617865 is an apocalyptic number.

165617865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165617865 is an abundant number, since it is smaller than the sum of its proper divisors (174978423).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165617865 is an frugal number, since it uses more digits than its factorization.

165617865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6521 (or 6506 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The square root of 165617865 is about 12869.2604682631. The cubic root of 165617865 is about 549.1644226675.

The spelling of 165617865 in words is "one hundred sixty-five million, six hundred seventeen thousand, eight hundred sixty-five".