666492464294665 has 4 divisors (see below), whose sum is σ = 799790957153604. Its totient is φ = 533193971435728.

The previous prime is 666492464294621. The next prime is 666492464294801. The reversal of 666492464294665 is 566492464294666.

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

It can be written as a sum of positive squares in 2 ways, for example, as 398262850162576 + 268229614132089 = 19956524^2 + 16377717^2 .

It is a cyclic number.

It is not a de Polignac number, because 666492464294665 - 2²⁵ = 666492430740233 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66649246429462 + ... + 66649246429471.

It is an arithmetic number, because the mean of its divisors is an integer number (199947739288401).

Almost surely, 2^{666492464294665} is an apocalyptic number.

It is an amenable number.

666492464294665 is a deficient number, since it is larger than the sum of its proper divisors (133298492858939).

666492464294665 is a wasteful number, since it uses less digits than its factorization.

666492464294665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133298492858938.

The product of its digits is 19349176320, while the sum is 79.

Subtracting from 666492464294665 its reverse (566492464294666), we obtain a palindrome (99999999999999).

The spelling of 666492464294665 in words is "six hundred sixty-six trillion, four hundred ninety-two billion, four hundred sixty-four million, two hundred ninety-four thousand, six hundred sixty-five".