9978376475681 has 16 divisors (see below), whose sum is σ = 10118680830720. Its totient is φ = 9838968289920.

The previous prime is 9978376475629. The next prime is 9978376475747. The reversal of 9978376475681 is 1865746738799.

It is a cyclic number.

It is not a de Polignac number, because 9978376475681 - 2²² = 9978372281377 is a prime.

It is a super-2 number, since 2×9978376475681² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 9978376475596 and 9978376475605.

It is not an unprimeable number, because it can be changed into a prime (9978376475381) 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, 334459541 + ... + 334489373.

It is an arithmetic number, because the mean of its divisors is an integer number (632417551920).

Almost surely, 2^{9978376475681} is an apocalyptic number.

It is an amenable number.

9978376475681 is a deficient number, since it is larger than the sum of its proper divisors (140304355039).

9978376475681 is a wasteful number, since it uses less digits than its factorization.

9978376475681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44696.

The product of its digits is 3840721920, while the sum is 80.

The spelling of 9978376475681 in words is "nine trillion, nine hundred seventy-eight billion, three hundred seventy-six million, four hundred seventy-five thousand, six hundred eighty-one".