165211121 has 8 divisors (see below), whose sum is σ = 170873088. Its totient is φ = 159570000.

The previous prime is 165211019. The next prime is 165211141. The reversal of 165211121 is 121112561.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165211121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165211093 and 165211102.

It is not an unprimeable number, because it can be changed into a prime (165211141) 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 7 ways as a sum of consecutive naturals, for example, 11846 + ... + 21696.

It is an arithmetic number, because the mean of its divisors is an integer number (21359136).

Almost surely, 2^165211121 is an apocalyptic number.

It is an amenable number.

165211121 is a deficient number, since it is larger than the sum of its proper divisors (5661967).

165211121 is an equidigital number, since it uses as much as digits as its factorization.

165211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10423.

The product of its digits is 120, while the sum is 20.

The square root of 165211121 is about 12853.4478253891. The cubic root of 165211121 is about 548.7144864186.

Adding to 165211121 its reverse (121112561), we get a palindrome (286323682).

The spelling of 165211121 in words is "one hundred sixty-five million, two hundred eleven thousand, one hundred twenty-one".