165616405 has 16 divisors (see below), whose sum is σ = 201003264. Its totient is φ = 130993920.

The previous prime is 165616387. The next prime is 165616427. The reversal of 165616405 is 504616561.

It is a happy number.

It is not a de Polignac number, because 165616405 - 2⁷ = 165616277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200824 + ... + 201646.

It is an arithmetic number, because the mean of its divisors is an integer number (12562704).

Almost surely, 2^165616405 is an apocalyptic number.

It is an amenable number.

165616405 is a deficient number, since it is larger than the sum of its proper divisors (35386859).

165616405 is a wasteful number, since it uses less digits than its factorization.

165616405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 165616405 is about 12869.2037438219. The cubic root of 165616405 is about 549.1628089478.

The spelling of 165616405 in words is "one hundred sixty-five million, six hundred sixteen thousand, four hundred five".