165864215 has 16 divisors (see below), whose sum is σ = 217502496. Its totient is φ = 120422400.

The previous prime is 165864211. The next prime is 165864217. The reversal of 165864215 is 512468561.

It is a happy number.

It is not a de Polignac number, because 165864215 - 2² = 165864211 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165864211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34775 + ... + 39255.

It is an arithmetic number, because the mean of its divisors is an integer number (13593906).

Almost surely, 2^165864215 is an apocalyptic number.

165864215 is a deficient number, since it is larger than the sum of its proper divisors (51638281).

165864215 is a wasteful number, since it uses less digits than its factorization.

165864215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5170.

The product of its digits is 57600, while the sum is 38.

The square root of 165864215 is about 12878.8281687427. The cubic root of 165864215 is about 549.4365745336.

The spelling of 165864215 in words is "one hundred sixty-five million, eight hundred sixty-four thousand, two hundred fifteen".