666034721623171 has 4 divisors (see below), whose sum is σ = 667943130568000. Its totient is φ = 664126312678344.

The previous prime is 666034721623153. The next prime is 666034721623247. The reversal of 666034721623171 is 171326127430666.

666034721623171 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 666034721623171 - 2²³ = 666034713234563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666034721623151) 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, 954204471891 + ... + 954204472588.

It is an arithmetic number, because the mean of its divisors is an integer number (166985782642000).

Almost surely, 2^{666034721623171} is an apocalyptic number.

666034721623171 is a deficient number, since it is larger than the sum of its proper divisors (1908408944829).

666034721623171 is a wasteful number, since it uses less digits than its factorization.

666034721623171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1908408944828.

The product of its (nonzero) digits is 9144576, while the sum is 55.

The spelling of 666034721623171 in words is "six hundred sixty-six trillion, thirty-four billion, seven hundred twenty-one million, six hundred twenty-three thousand, one hundred seventy-one".