668712849849 has 16 divisors (see below), whose sum is σ = 1080748040640. Its totient is φ = 405280514880.

The previous prime is 668712849797. The next prime is 668712849851. The reversal of 668712849849 is 948948217866.

668712849849 is a `hidden beast` number, since 6 + 6 + 8 + 7 + 128 + 498 + 4 + 9 = 666.

668712849849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 668712849849 - 2¹² = 668712845753 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (668712848849) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1125778912 + ... + 1125779505.

It is an arithmetic number, because the mean of its divisors is an integer number (67546752540).

Almost surely, 2^668712849849 is an apocalyptic number.

It is an amenable number.

668712849849 is a deficient number, since it is larger than the sum of its proper divisors (412035190791).

668712849849 is a wasteful number, since it uses less digits than its factorization.

668712849849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2251558437 (or 2251558431 counting only the distinct ones).

The product of its digits is 334430208, while the sum is 72.

The spelling of 668712849849 in words is "six hundred sixty-eight billion, seven hundred twelve million, eight hundred forty-nine thousand, eight hundred forty-nine".