165405211 has 8 divisors (see below), whose sum is σ = 167484240. Its totient is φ = 163336608.

The previous prime is 165405199. The next prime is 165405217. The reversal of 165405211 is 112504561.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165405211 - 2⁵ = 165405179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165405217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32160 + ... + 36946.

It is an arithmetic number, because the mean of its divisors is an integer number (20935530).

Almost surely, 2^165405211 is an apocalyptic number.

165405211 is a deficient number, since it is larger than the sum of its proper divisors (2079029).

165405211 is a wasteful number, since it uses less digits than its factorization.

165405211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5213.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 165405211 is about 12860.9957235045. The cubic root of 165405211 is about 548.9292788930.

Adding to 165405211 its reverse (112504561), we get a palindrome (277909772).

The spelling of 165405211 in words is "one hundred sixty-five million, four hundred five thousand, two hundred eleven".