165261664 has 24 divisors (see below), whose sum is σ = 330219288. Its totient is φ = 81396480.

The previous prime is 165261661. The next prime is 165261673. The reversal of 165261664 is 466162561.

It is a super-2 number, since 2×165261664² = 54622835176097792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165261661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36397 + ... + 40684.

It is an arithmetic number, because the mean of its divisors is an integer number (13759137).

Almost surely, 2^165261664 is an apocalyptic number.

It is an amenable number.

165261664 is a deficient number, since it is larger than the sum of its proper divisors (164957624).

165261664 is an equidigital number, since it uses as much as digits as its factorization.

165261664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77158 (or 77150 counting only the distinct ones).

The product of its digits is 51840, while the sum is 37.

The square root of 165261664 is about 12855.4138011968. The cubic root of 165261664 is about 548.7704367453.

The spelling of 165261664 in words is "one hundred sixty-five million, two hundred sixty-one thousand, six hundred sixty-four".