165830421 has 4 divisors (see below), whose sum is σ = 221107232. Its totient is φ = 110553612.

The previous prime is 165830383. The next prime is 165830447. The reversal of 165830421 is 124038561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 165830421 - 2¹¹ = 165828373 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 (165830321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27638401 + ... + 27638406.

It is an arithmetic number, because the mean of its divisors is an integer number (55276808).

Almost surely, 2^165830421 is an apocalyptic number.

It is an amenable number.

165830421 is a deficient number, since it is larger than the sum of its proper divisors (55276811).

165830421 is an equidigital number, since it uses as much as digits as its factorization.

165830421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55276810.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 165830421 is about 12877.5161036591. The cubic root of 165830421 is about 549.3992570191.

Adding to 165830421 its reverse (124038561), we get a palindrome (289868982).

The spelling of 165830421 in words is "one hundred sixty-five million, eight hundred thirty thousand, four hundred twenty-one".