666287426506727 has 4 divisors (see below), whose sum is σ = 681782482937160. Its totient is φ = 650792370076296.

The previous prime is 666287426506643. The next prime is 666287426506763. The reversal of 666287426506727 is 727605624782666.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666287426506727 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 (666287426502727) 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, 7747528215152 + ... + 7747528215237.

It is an arithmetic number, because the mean of its divisors is an integer number (170445620734290).

Almost surely, 2^{666287426506727} is an apocalyptic number.

666287426506727 is a deficient number, since it is larger than the sum of its proper divisors (15495056430433).

666287426506727 is a wasteful number, since it uses less digits than its factorization.

666287426506727 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15495056430432.

The product of its (nonzero) digits is 3413975040, while the sum is 74.

The spelling of 666287426506727 in words is "six hundred sixty-six trillion, two hundred eighty-seven billion, four hundred twenty-six million, five hundred six thousand, seven hundred twenty-seven".