165820123 has 8 divisors (see below), whose sum is σ = 189690848. Its totient is φ = 141994944.

The previous prime is 165820121. The next prime is 165820129. The reversal of 165820123 is 321028561.

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

It is not a de Polignac number, because 165820123 - 2¹ = 165820121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165820091 and 165820100.

It is not an unprimeable number, because it can be changed into a prime (165820121) 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, 3186 + ... + 18487.

It is an arithmetic number, because the mean of its divisors is an integer number (23711356).

Almost surely, 2^165820123 is an apocalyptic number.

165820123 is a deficient number, since it is larger than the sum of its proper divisors (23870725).

165820123 is a wasteful number, since it uses less digits than its factorization.

165820123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22773.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 165820123 is about 12877.1162532611. The cubic root of 165820123 is about 549.3878842954.

Adding to 165820123 its reverse (321028561), we get a palindrome (486848684).

The spelling of 165820123 in words is "one hundred sixty-five million, eight hundred twenty thousand, one hundred twenty-three".