664865883431 has 16 divisors (see below), whose sum is σ = 675273291264. Its totient is φ = 654539919264.

The previous prime is 664865883403. The next prime is 664865883449. The reversal of 664865883431 is 134388568466.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664865883431 is a prime.

It is a super-4 number, since 4×664865883431⁴ (a number of 48 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664865883481) 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, 26426600 + ... + 26451746.

It is an arithmetic number, because the mean of its divisors is an integer number (42204580704).

Almost surely, 2^664865883431 is an apocalyptic number.

664865883431 is a deficient number, since it is larger than the sum of its proper divisors (10407407833).

664865883431 is a wasteful number, since it uses less digits than its factorization.

664865883431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26750.

The product of its digits is 79626240, while the sum is 62.

The spelling of 664865883431 in words is "six hundred sixty-four billion, eight hundred sixty-five million, eight hundred eighty-three thousand, four hundred thirty-one".