800666372781 has 48 divisors (see below), whose sum is σ = 1304718083200. Its totient is φ = 484914133440.

The previous prime is 800666372767. The next prime is 800666372813. The reversal of 800666372781 is 187273666008.

It is not a de Polignac number, because 800666372781 - 2¹⁵ = 800666340013 is a prime.

It is a super-2 number, since 2×800666372781² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (800666372711) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4642665 + ... + 4812033.

Almost surely, 2^800666372781 is an apocalyptic number.

It is an amenable number.

800666372781 is a deficient number, since it is larger than the sum of its proper divisors (504051710419).

800666372781 is a wasteful number, since it uses less digits than its factorization.

800666372781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170847 (or 170830 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 54.

The spelling of 800666372781 in words is "eight hundred billion, six hundred sixty-six million, three hundred seventy-two thousand, seven hundred eighty-one".