666993456351 has 6 divisors (see below), whose sum is σ = 963434992520. Its totient is φ = 444662304228.

The previous prime is 666993456341. The next prime is 666993456373. The reversal of 666993456351 is 153654399666.

It is a happy number.

It is not a de Polignac number, because 666993456351 - 2⁵ = 666993456319 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 (666993456341) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37055192011 + ... + 37055192028.

Almost surely, 2^666993456351 is an apocalyptic number.

666993456351 is a deficient number, since it is larger than the sum of its proper divisors (296441536169).

666993456351 is a wasteful number, since it uses less digits than its factorization.

666993456351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74110384045 (or 74110384042 counting only the distinct ones).

The product of its digits is 94478400, while the sum is 63.

The spelling of 666993456351 in words is "six hundred sixty-six billion, nine hundred ninety-three million, four hundred fifty-six thousand, three hundred fifty-one".