39664246693 has 4 divisors (see below), whose sum is σ = 39700013580. Its totient is φ = 39628479808.

The previous prime is 39664246669. The next prime is 39664246757.

39664246693 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6510391969 + 33153854724 = 80687^2 + 182082^2 .

It is a cyclic number.

It is not a de Polignac number, because 39664246693 - 2²⁵ = 39630692261 is a prime.

It is a super-2 number, since 2×39664246693² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39664246793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17881780 + ... + 17883997.

It is an arithmetic number, because the mean of its divisors is an integer number (9925003395).

Almost surely, 2^39664246693 is an apocalyptic number.

It is an amenable number.

39664246693 is a deficient number, since it is larger than the sum of its proper divisors (35766887).

39664246693 is a wasteful number, since it uses less digits than its factorization.

39664246693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35766886.

The product of its digits is 30233088, while the sum is 58.

The spelling of 39664246693 in words is "thirty-nine billion, six hundred sixty-four million, two hundred forty-six thousand, six hundred ninety-three".