665512173 has 8 divisors (see below), whose sum is σ = 985944000. Its totient is φ = 443674764.

The previous prime is 665512171. The next prime is 665512189. The reversal of 665512173 is 371215566.

It is not a de Polignac number, because 665512173 - 2¹ = 665512171 is a prime.

It is a super-2 number, since 2×665512173² = 885812904822363858, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665512171) 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, 12324273 + ... + 12324326.

It is an arithmetic number, because the mean of its divisors is an integer number (123243000).

Almost surely, 2^665512173 is an apocalyptic number.

It is an amenable number.

665512173 is a deficient number, since it is larger than the sum of its proper divisors (320431827).

665512173 is a wasteful number, since it uses less digits than its factorization.

665512173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24648608 (or 24648602 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The square root of 665512173 is about 25797.5226136154. The cubic root of 665512173 is about 873.0759018098.

The spelling of 665512173 in words is "six hundred sixty-five million, five hundred twelve thousand, one hundred seventy-three".