165508481 has 16 divisors (see below), whose sum is σ = 183209040. Its totient is φ = 148807680.

The previous prime is 165508477. The next prime is 165508489. The reversal of 165508481 is 184805561.

It can be written as a sum of positive squares in 8 ways, for example, as 128881 + 165379600 = 359^2 + 12860^2 .

It is a cyclic number.

It is not a de Polignac number, because 165508481 - 2² = 165508477 is a prime.

It is a super-2 number, since 2×165508481² = 54786114565854722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165508489) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46091 + ... + 49551.

It is an arithmetic number, because the mean of its divisors is an integer number (11450565).

Almost surely, 2^165508481 is an apocalyptic number.

It is an amenable number.

165508481 is a deficient number, since it is larger than the sum of its proper divisors (17700559).

165508481 is a wasteful number, since it uses less digits than its factorization.

165508481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3604.

The product of its (nonzero) digits is 38400, while the sum is 38.

The square root of 165508481 is about 12865.0099494715. The cubic root of 165508481 is about 549.0434956354.

The spelling of 165508481 in words is "one hundred sixty-five million, five hundred eight thousand, four hundred eighty-one".