664165617 has 8 divisors (see below), whose sum is σ = 888064224. Its totient is φ = 441522048.

The previous prime is 664165609. The next prime is 664165633. The reversal of 664165617 is 716561466.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 664165617 - 2³ = 664165609 is a prime.

It is a super-2 number, since 2×664165617² = 882231933609981378, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664165657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 312523 + ... + 314640.

It is an arithmetic number, because the mean of its divisors is an integer number (111008028).

Almost surely, 2^664165617 is an apocalyptic number.

It is an amenable number.

664165617 is a deficient number, since it is larger than the sum of its proper divisors (223898607).

664165617 is a wasteful number, since it uses less digits than its factorization.

664165617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627519.

The product of its digits is 181440, while the sum is 42.

The square root of 664165617 is about 25771.4108461295. The cubic root of 664165617 is about 872.4866617009.

The spelling of 664165617 in words is "six hundred sixty-four million, one hundred sixty-five thousand, six hundred seventeen".