66642647879 has 8 divisors (see below), whose sum is σ = 67339935600. Its totient is φ = 65945569536.

The previous prime is 66642647873. The next prime is 66642647899. The reversal of 66642647879 is 97874624666.

66642647879 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 66642647879 - 2⁸ = 66642647623 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 (66642647873) 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, 634397 + ... + 731945.

It is an arithmetic number, because the mean of its divisors is an integer number (8417491950).

Almost surely, 2^66642647879 is an apocalyptic number.

66642647879 is a deficient number, since it is larger than the sum of its proper divisors (697287721).

66642647879 is an equidigital number, since it uses as much as digits as its factorization.

66642647879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104689.

The product of its digits is 146313216, while the sum is 65.

The spelling of 66642647879 in words is "sixty-six billion, six hundred forty-two million, six hundred forty-seven thousand, eight hundred seventy-nine".