165404 has 6 divisors (see below), whose sum is σ = 289464. Its totient is φ = 82700.

The previous prime is 165397. The next prime is 165437. The reversal of 165404 is 404561.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20672 + ... + 20679.

It is an arithmetic number, because the mean of its divisors is an integer number (48244).

2¹⁶⁵⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

165404 is a deficient number, since it is larger than the sum of its proper divisors (124060).

165404 is a wasteful number, since it uses less digits than its factorization.

165404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41355 (or 41353 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 165404 is about 406.6989058259. The cubic root of 165404 is about 54.8927939244.

Adding to 165404 its reverse (404561), we get a palindrome (569965).

The spelling of 165404 in words is "one hundred sixty-five thousand, four hundred four".