6378397923681 has 48 divisors (see below), whose sum is σ = 10957727289600. Its totient is φ = 3498043377024.

The previous prime is 6378397923647. The next prime is 6378397923683. The reversal of 6378397923681 is 1863297938736.

6378397923681 is a `hidden beast` number, since 6 + 3 + 78 + 397 + 92 + 3 + 6 + 81 = 666.

It is not a de Polignac number, because 6378397923681 - 2³³ = 6369807989089 is a prime.

It is a super-2 number, since 2×6378397923681² (a number of 26 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6378397923683) 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, 10147546 + ... + 10757763.

It is an arithmetic number, because the mean of its divisors is an integer number (228285985200).

Almost surely, 2^{6378397923681} is an apocalyptic number.

It is an amenable number.

6378397923681 is a deficient number, since it is larger than the sum of its proper divisors (4579329365919).

6378397923681 is a wasteful number, since it uses less digits than its factorization.

6378397923681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20905518 (or 20905515 counting only the distinct ones).

The product of its digits is 493807104, while the sum is 72.

The spelling of 6378397923681 in words is "six trillion, three hundred seventy-eight billion, three hundred ninety-seven million, nine hundred twenty-three thousand, six hundred eighty-one".