66736668579839 has 4 divisors (see below), whose sum is σ = 66736718906856. Its totient is φ = 66736618252824.

The previous prime is 66736668579829. The next prime is 66736668579857. The reversal of 66736668579839 is 93897586663766.

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

It is a cyclic number.

It is not a de Polignac number, because 66736668579839 - 2¹⁶ = 66736668514303 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 (66736668579829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23119049 + ... + 25844994.

It is an arithmetic number, because the mean of its divisors is an integer number (16684179726714).

Almost surely, 2^{66736668579839} is an apocalyptic number.

66736668579839 is a deficient number, since it is larger than the sum of its proper divisors (50327017).

66736668579839 is a wasteful number, since it uses less digits than its factorization.

66736668579839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50327016.

The product of its digits is 88885278720, while the sum is 89.

The spelling of 66736668579839 in words is "sixty-six trillion, seven hundred thirty-six billion, six hundred sixty-eight million, five hundred seventy-nine thousand, eight hundred thirty-nine".