979889863681 has 4 divisors (see below), whose sum is σ = 979905284100. Its totient is φ = 979874443264.

The previous prime is 979889863679. The next prime is 979889863697. The reversal of 979889863681 is 186368988979.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 443567988081 + 536321875600 = 666009^2 + 732340^2 .

It is a cyclic number.

It is not a de Polignac number, because 979889863681 - 2¹ = 979889863679 is a prime.

It is a super-2 number, since 2×979889863681² (a number of 25 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 = 979889863595 and 979889863604.

It is not an unprimeable number, because it can be changed into a prime (979889860681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7614496 + ... + 7742113.

It is an arithmetic number, because the mean of its divisors is an integer number (244976321025).

Almost surely, 2^979889863681 is an apocalyptic number.

It is an amenable number.

979889863681 is a deficient number, since it is larger than the sum of its proper divisors (15420419).

979889863681 is a wasteful number, since it uses less digits than its factorization.

979889863681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15420418.

The product of its digits is 2257403904, while the sum is 82.

The spelling of 979889863681 in words is "nine hundred seventy-nine billion, eight hundred eighty-nine million, eight hundred sixty-three thousand, six hundred eighty-one".