664685869 has 8 divisors (see below), whose sum is σ = 670619648. Its totient is φ = 658763280.

The previous prime is 664685863. The next prime is 664685881. The reversal of 664685869 is 968586466.

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

It is a cyclic number.

It is not a de Polignac number, because 664685869 - 2⁵ = 664685837 is a prime.

It is a super-2 number, since 2×664685869² = 883614608896570322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664685863) 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, 154984 + ... + 159214.

It is an arithmetic number, because the mean of its divisors is an integer number (83827456).

Almost surely, 2^664685869 is an apocalyptic number.

It is an amenable number.

664685869 is a deficient number, since it is larger than the sum of its proper divisors (5933779).

664685869 is a wasteful number, since it uses less digits than its factorization.

664685869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5595.

The product of its digits is 14929920, while the sum is 58.

The square root of 664685869 is about 25781.5024581579. The cubic root of 664685869 is about 872.7144133598.

The spelling of 664685869 in words is "six hundred sixty-four million, six hundred eighty-five thousand, eight hundred sixty-nine".