165223805 has 4 divisors (see below), whose sum is σ = 198268572. Its totient is φ = 132179040.

The previous prime is 165223801. The next prime is 165223811. The reversal of 165223805 is 508322561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 92871769 + 72352036 = 9637^2 + 8506^2 .

It is not a de Polignac number, because 165223805 - 2² = 165223801 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 (165223801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16522376 + ... + 16522385.

It is an arithmetic number, because the mean of its divisors is an integer number (49567143).

Almost surely, 2^165223805 is an apocalyptic number.

It is an amenable number.

165223805 is a deficient number, since it is larger than the sum of its proper divisors (33044767).

165223805 is an equidigital number, since it uses as much as digits as its factorization.

165223805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33044766.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 165223805 is about 12853.9412243872. The cubic root of 165223805 is about 548.7285284846.

The spelling of 165223805 in words is "one hundred sixty-five million, two hundred twenty-three thousand, eight hundred five".