66858577585867 has 4 divisors (see below), whose sum is σ = 70791435090936. Its totient is φ = 62925720080800.

The previous prime is 66858577585847. The next prime is 66858577585897. The reversal of 66858577585867 is 76858577585866.

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 66858577585867 - 2⁴³ = 58062484563659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66858577585847) 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, 1966428752509 + ... + 1966428752542.

It is an arithmetic number, because the mean of its divisors is an integer number (17697858772734).

Almost surely, 2^{66858577585867} is an apocalyptic number.

66858577585867 is a deficient number, since it is larger than the sum of its proper divisors (3932857505069).

66858577585867 is a wasteful number, since it uses less digits than its factorization.

66858577585867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3932857505068.

The product of its digits is 189665280000, while the sum is 91.

Subtracting 66858577585867 from its reverse (76858577585866), we obtain a palindrome (9999999999999).

The spelling of 66858577585867 in words is "sixty-six trillion, eight hundred fifty-eight billion, five hundred seventy-seven million, five hundred eighty-five thousand, eight hundred sixty-seven".