664761718333439 has 8 divisors (see below), whose sum is σ = 668753300482848. Its totient is φ = 660770266816000.

The previous prime is 664761718333411. The next prime is 664761718333463. The reversal of 664761718333439 is 934333817167466.

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 664761718333439 - 2⁸ = 664761718333183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664761718333639) 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, 22440242 + ... + 42814575.

It is an arithmetic number, because the mean of its divisors is an integer number (83594162560356).

Almost surely, 2^{664761718333439} is an apocalyptic number.

664761718333439 is a deficient number, since it is larger than the sum of its proper divisors (3991582149409).

664761718333439 is a wasteful number, since it uses less digits than its factorization.

664761718333439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65315985.

The product of its digits is 987614208, while the sum is 71.

The spelling of 664761718333439 in words is "six hundred sixty-four trillion, seven hundred sixty-one billion, seven hundred eighteen million, three hundred thirty-three thousand, four hundred thirty-nine".